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August 2026
- 2 participants
- 3 discussions
Hi!
Due to logistics mistake, the pigeonhole tarball was reuploaded now to include man pages that had dropped out by mistake. No code changes or git changes sneaked in.
Sorry for the inconvenience.
Aki
1
0
Hi!
We're sharing our latest advisory with you and like to thank everyone who contributed in finding and solving those vulnerabilities. This advisory will also be published at https://documentation.open-xchange.com/dovecot/security/advisories/html/202…
---
Classification: TLP:GREEN
Internal reference: DOV-8476
Type: CWE-403 (Exposure of File Descriptor to Unintended Control Sphere ('File Descriptor Leak'))
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2025-11-25
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-33263
CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L)
Details:
submission-login: Panic when mail_max_userip_connections is reached: Panic: epoll_ctl(del, 8) failed: Bad file descriptor. When mail_max_userip_connections is set (defaul
t 10) and reached, submission-login can crash with epoll() panic caused by file descriptor handling issues.
Risk:
If running in high-security mode (default for community releases), only the new submission connection gets terminated. If running in high-performance mode (default for Pr
o releases), all connections handled by the submission-login process will be terminated. The crashes can cause failure for user to send a message, or it can cause duplica
te messages to be sent. If TLS is not used (in the backend server processing the submission), duplicate deliveries cannot happen, because the crash can only happen at AUT
H stage. No publicly available exploits are known.
Solution:
Limit the number of connections handled by single submission-login process. This has a performance impact though. Update to non-vulnerable version.
---
Internal reference: DOV-8874
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-03-11
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ylwango613@yeswehack
CVE: CVE-2026-33607
CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L)
Details:
Dovecot IMAP LIST match_sub() Exponential Backtracking — CPU Denial of Service. An attacker that has valid credentials can use IMAP LIST command to consume CPU.
Risk:
This can cause degradation or denial of service for IMAP. No publicly available exploits are known.
Solution:
Monitor system for abnormal CPU usage and kill the offending process and lock account. Alternatively install fixed version.
---
Internal reference: DOV-8884
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-03-13
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-27852
CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Details:
DoS by sending mail with bad header. An attacker that can send mail to a user can craft a message whose headers contain a very large number of email addresses or MIME par
ameters, which causes excessive memory usage when the message is later parsed.
Risk:
The message is still delivered, but reading it over IMAP can exhaust the memory limit of the process and terminate it, causing denial of service for the affected user. No
publicly available exploits are known.
Solution:
Update to non-vulnerable version.
---
Internal reference: DOV-8941
Type: CWE-93 (Improper Neutralization of CRLF Sequences ('CRLF Injection'))
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-03-24
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: thanos_haruki@yeswehack
CVE: CVE-2026-33606
CVSS: 4.8 (CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:N/I:H/A:N)
Details:
dsync: Mail content can cause dsync protocol injection. Mail content stored by a user can be crafted so that it is interpreted as dsync protocol commands when an administ
rator later runs dsync with the stream protocol, for example during a migration.
Risk:
Injected commands can modify mailbox state on the destination during migration or replication, including internal mailbox attributes that a user should not be able to set
directly. It can also cause dsync errors. No publicly available exploits are known.
Solution:
Avoid running dsync with the stream protocol on mailboxes with untrusted content. Update to non-vulnerable version.
---
Internal reference: DOV-8947
Type: CWE-655 (Insufficient Psychological Acceptability)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-03-24
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: heckintosh@yeswehack
CVE: CVE-2026-33604
CVSS: 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N)
Details:
SMTP Smuggling via Missing Dot-Stuffing After Bare Carriage Return. An attacker that can get Dovecot to relay a message, for example through Sieve redirect or submission
relay, can use a crafted line ending in the message body to bypass the outbound protection that prevents message content from being interpreted as SMTP commands.
Risk:
A downstream mail server that hasn't yet fixed the SMTP smuggling vulnerability can be tricked into treating part of the message body as new SMTP commands, allowing injec
tion of spoofed email. This is the same vulnerability class as CVE-2023-51764 and CVE-2023-51766. No publicly available exploits are known.
Solution:
Where you control the receiving mail servers, ensure they reject bare carriage returns in message data. Update to non-vulnerable version.
---
Internal reference: DOV-8949
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-03-24
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: djvirus@yeswehack
CVE: CVE-2026-40014
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H)
Details:
IMAP THREAD REFERENCES O(N²) CPU DoS via Crafted References Header (index-thread-links.c). An attacker that can send mail to a user can craft a message header that makes
the IMAP THREAD command consume CPU disproportionate to the size of the message.
Risk:
When a mail client issues a THREAD command on the affected mailbox, this can cause degradation or denial of service for IMAP. No publicly available exploits are known.
Solution:
Monitor system for abnormal CPU usage, kill the offending process and remove the offending message from the affected mailbox. Update to non-vulnerable version.
---
Internal reference: DOV-8991
Type: CWE-124 (Buffer Underwrite ('Buffer Underflow'))
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-02
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilyar@yeswehack
CVE: CVE-2026-40013
CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L)
Details:
pigeonhole: Stack Buffer Underflow in Pigeonhole ManageSieve CHECKSCRIPT/PUTSCRIPT. An attacker that has valid credentials can submit a Sieve script containing an extreme
numeric literal, which causes an out-of-bounds write when the ManageSieve service compiles the script.
Risk:
This causes memory corruption and an observed crash of the ManageSieve process, resulting in denial of service for script management. This might be able to be used for re
mote code execution. No publicly available exploits are known.
Solution:
Disable the ManageSieve service if users do not need remote Sieve script management. Update to non-vulnerable version.
---
Internal reference: DOV-8994
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-02
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilyar@yeswehack
CVE: CVE-2026-33605
CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Details:
managesieve-login: Pre-auth crash. An unauthenticated attacker can crash the ManageSieve login process by sending a small malformed command before authenticating.
Risk:
If running in high-security mode (default for community releases), only the attacker's own connection is terminated. If running in high-performance mode (default for Pro
releases), all connections handled by the same managesieve-login process are terminated. Repeating the attack can cause denial of service for Sieve script management. No
publicly available exploits are known.
Solution:
Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable version.
---
Internal reference: DOV-9039
Type: CWE-89 (Improper Neutralization of Special Elements used in an SQL Command ('SQL Injection'))
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-08
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: tipsennn@yeswehack
CVE: CVE-2026-40018
CVSS: 7.4 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)
Details:
MySQL multi-byte escaping wrong. None
Risk:
None No publicly available exploits are known.
Solution:
None
---
Internal reference: DOV-9041
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot CE core >=2.4.3 <2.4.5
First fixed revision: OX Dovecot CE core 2.4.5
Discovery date: 2026-04-08
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilyar@yeswehack
CVE: CVE-2026-40019
CVSS: 5.9 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:H)
Details:
v2.4.3 regression: managesieve-login pre-auth infinite loop. An unauthenticated attacker can send a truncated quoted argument to the ManageSieve login process, which make
s it spin in an infinite loop consuming CPU.
Risk:
This can cause degradation or denial of service for Sieve script management, and repeated connections can consume all available CPU on the server. No publicly available e
xploits are known.
Solution:
Monitor system for abnormal CPU usage and kill the offending process. Restrict network access to the ManageSieve service to trusted clients. Update to non-vulnerable vers
ion.
---
Internal reference: DOV-9046
Type: CWE-125 (Out-of-bounds Read)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-08
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: tipsennn@yeswehack
CVE: CVE-2026-40015
CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L)
Details:
imap-hibernate can be crashed. An attacker that has valid credentials can open many connections to the imap-hibernate service and send invalid commands, which can intermi
ttently cause an out-of-bounds read and crash the process.
Risk:
The crash interrupts hibernated IMAP sessions handled by the affected process, which can cause degradation of service for IMAP. No publicly available exploits are known.
Solution:
Disable IMAP hibernation. Update to non-vulnerable version.
---
Internal reference: DOV-9047
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-08
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: djvirus@yeswehack
CVE: CVE-2026-40017
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H)
Details:
IMAP THREAD O(M³) CPU DoS via CRC32 Hash Collision in strmap (mail-index-strmap.c / hash2.c). An attacker that can send mail to a user can craft a message header whose va
lues are chosen to collide in an internal hash table, which makes the IMAP THREAD command consume CPU disproportionate to the size of the message. This is a separate issu
e from CVE-2026-40014 and is not addressed by that fix.
Risk:
Whenever a mail client issues a THREAD command on the affected mailbox, this can cause degradation or denial of service for IMAP. No publicly available exploits are known
.
Solution:
Monitor system for abnormal CPU usage, kill the offending process and remove the offending message from the affected mailbox. Update to non-vulnerable version.
---
Internal reference: DOV-9066
Type: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-12
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilhamaf@yeswehack
CVE: CVE-2026-40203
CVSS: 3.7 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N)
Details:
IMAP Compression Can Reveal Whether a Small Synced Email Body Matches Sender-Chosen Text. When IMAP compression is enabled, the same compression state is reused across re
sponses in a session, so response sizes depend on both attacker-supplied mail and other mail in the same mailbox.
Risk:
An attacker that can send mail to a user and can also observe the sizes of that user's IMAP traffic can confirm whether the body of a small message matches a guessed text
. Recovery of arbitrary unknown content was not demonstrated, but the attack can disclose whether a secret-like message body matches a candidate. No publicly available ex
ploits are known.
Solution:
Disable IMAP compression. Update to non-vulnerable version.
---
Internal reference: DOV-9070
Type: CWE-416 (Use After Free)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-14
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilyar@yeswehack
CVE: CVE-2026-42007
CVSS: 9.1 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:H)
Details:
Sieve editheader RCE. An attacker that has valid credentials can use a Sieve script with the editheader extension to trigger a use-after-free in the mail editing code, an
d to write memory contents beyond the intended buffer into the delivered mail.
Risk:
This causes memory leak and opportunity to do memory corruption during mail delivery, which can crash the delivery process and may allow execution of arbitrary code in th
e context of that process. No publicly available exploits are known.
Solution:
Disable the Sieve editheader extension. Update to non-vulnerable version.
---
Internal reference: DOV-9099
Type: CWE-284 (Improper Access Control)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-22
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilhamaf@yeswehack
CVE: CVE-2026-40204
CVSS: 3.1 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:L/A:N)
Details:
acl: lda_mailbox_autocreate can bypass acl restrictions. None
Risk:
None No publicly available exploits are known.
Solution:
None
---
Internal reference: DOV-9106
Type: CWE-287 (Improper Authentication)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.11.2 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.11.2 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-23
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: Noobosaurus@yeswehack
CVE: CVE-2026-40205
CVSS: 5.9 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:H/A:N)
Details:
OAuth2 passdb scope enforcement bypass via OR semantics in remote validation path. An attacker that holds an OAuth2 token granting only part of the required scopes can au
thenticate, because when more than one scope is required in the configuration, the remote token validation paths accept a token that carries only one of them, while the l
ocal token validation path correctly requires all of them.
Risk:
The configured authorization policy is not enforced, so a token that was granted only part of the required permissions is accepted where it should have been rejected. No
publicly available exploits are known.
Solution:
Use local token validation where tokens can be validated locally. Update to non-vulnerable version.
---
Internal reference: DOV-9109
Type: CWE-287 (Improper Authentication)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.4 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.4 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-23
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-42008
CVSS: 4.3 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N)
Details:
XCLIENT FORWARD= bare token not namespaced, allows nopassword injection via trusted proxy. Forwarding information received from a host listed as a trusted proxy is not ke
pt separate from Dovecot's own authentication fields, so a value sent by that host can be injected as an internal authentication field.
Risk:
Any host permitted to act as a trusted proxy can authenticate as any user without knowing that user's password. This affects deployments whose password database honours a
field that permits authentication without a password. Deployments that do not configure trusted proxies are not affected. No publicly available exploits are known.
Solution:
Restrict the list of trusted proxy networks to hosts that are fully under your control. Update to non-vulnerable version.
---
Internal reference: DOV-9142
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-27
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: ilhamaf@yeswehack
CVE: CVE-2026-42395
CVSS: 4.3 (CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L)
Details:
Single NUL-Byte XCLIENT FORWARD Payload Crashes. A host listed as a trusted proxy can send forwarding information containing a NUL byte, which crashes the login process o
n the following login attempt.
Risk:
The login process is terminated, which can cause degradation or denial of service for logins. Deployments that do not configure trusted proxies are not affected. No publi
cly available exploits are known.
Solution:
Restrict the list of trusted proxy networks to hosts that are fully under your control. Update to non-vulnerable version.
---
Internal reference: DOV-9148
Type: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-04-27
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: D4RKCYPH3R@yeswehack
CVE: CVE-2026-42393
CVSS: 3.1 (CVSS:3.1/AV:A/AC:H/PR:N/UI:N/S:U/C:L/I:N/A:N)
Details:
doveadm_password or api key length can still be leaked with timing comparisons. The comparison used for the doveadm password and API key is not fully timing safe and can
reveal the length of the configured secret.
Risk:
An attacker with access to the same network as the doveadm service, able to make repeated requests and measure response timing accurately, can learn the length of the sec
ret, which reduces the effort needed to guess it. The secret value itself is not disclosed. No publicly available exploits are known.
Solution:
Restrict network access to the doveadm service to trusted clients. Update to non-vulnerable version.
---
Internal reference: DOV-9223
Type: CWE-1050 (Excessive Platform Resource Consumption within a Loop)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.15 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.15 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-05-05
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-52681
CVSS: 3.1 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:N/I:N/A:L)
Details:
Sieve resource usage tracking lost when active script changes. Sieve CPU resource usage is tracked in the compiled script, so an attacker that has valid credentials can r
eset the accounting by repeatedly changing the active script. Compiled script files are also not removed when a script is deleted or renamed.
Risk:
The configured Sieve CPU limit can be bypassed, allowing sustained CPU consumption, and the leftover files increase disk consumption. Both can cause degradation of servic
e for mail delivery. No publicly available exploits are known.
Solution:
Monitor system for abnormal CPU usage and disk consumption. Update to non-vulnerable version.
---
Internal reference: DOV-9230
Type: CWE-200 (Exposure of Sensitive Information to an Unauthorized Actor)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-05-06
Solution date: 2026-08-26
Disclosure date: 2026-08-26
Researcher credits: djvirus@yeswehack
CVE: CVE-2026-42392
CVSS: 4.3 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N)
Details:
imap-urlauth leaks memory into user-visible error messages. An attacker that has valid credentials can send an invalid IMAP URLFETCH command, which causes uninitialized m
emory to be included in the error response returned to the client.
Risk:
Process memory contents can be disclosed to the client, which may include sensitive data. No publicly available exploits are known.
Solution:
Disable the IMAP URLAUTH functionality. Update to non-vulnerable version.
---
Internal reference: DOV-9309
Type: CWE-287 (Improper Authentication)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.13 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.13 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-05-28
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-73208
CVSS: 7.4 (CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:N)
Details:
auth: db-oauth2: aud claim used as fallback for missing scope claim. An attacker that holds a token intended for a different purpose can authenticate, because when an OAu
th2 token response does not contain a scope claim, the audience claim is used in its place and checked against the configured required scopes. These are different concept
s, and the audience claim does not describe what a token is allowed to do.
Risk:
A token that grants no relevant permissions can be accepted because its intended recipient value happens to match a configured scope name, granting access that should hav
e been denied. It also hides an identity provider misconfiguration where scopes are not being issued at all. No publicly available exploits are known.
Solution:
Ensure the identity provider issues a scope claim for all tokens used with Dovecot, and that configured scope names do not match audience values. Update to non-vulnerable
version.
---
Internal reference: DOV-9401
Type: CWE-674 (Uncontrolled Recursion)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-06-10
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-73209
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Details:
imap-login crash: Self-recursion on zero-output decompress chunks. An attacker that has valid credentials can send crafted compressed data that causes the affected proces
s to exhaust its stack and crash.
Risk:
The affected process is terminated, which can cause degradation or denial of service for IMAP. No publicly available exploits are known.
Solution:
Update to non-vulnerable version.
---
Internal reference: DOV-9529
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.0 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.0 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-07-04
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-42391
CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H)
Details:
imap: Pre-login memory/CPU growth with ID command. An unauthenticated attacker can send an IMAP ID command with a very large number of parameters before logging in, which
causes memory and CPU usage to grow disproportionately.
Risk:
The login process can be terminated by the out-of-memory handling, which also terminates all other connections handled by the same process. This can cause degradation or
denial of service for IMAP logins. No publicly available exploits are known.
Solution:
Limit the number of connections handled by a single imap-login process. This has a performance impact though. Update to non-vulnerable version.
---
Internal reference: DOV-9530
Type: CWE-400 (Uncontrolled Resource Consumption)
Component: core
Report confidence: Confirmed
Solution status: Fixed by vendor
Affected versions: OX Dovecot Pro core >=2.3.11 <2.3.22.2, OX Dovecot Pro core >=3.0.0 <3.0.7, OX Dovecot Pro core >=3.1.0 <3.1.6, OX Dovecot CE core >=2.3.11 <2.4.5
First fixed revision: OX Dovecot Pro core 3.0.7, OX Dovecot Pro core 2.3.22.2, OX Dovecot Pro core 3.1.6, OX Dovecot CE core 2.4.5
Discovery date: 2026-07-04
Solution date: 2026-08-26
Disclosure date: 2026-08-26
CVE: CVE-2026-52687
CVSS: 6.5 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Details:
IMAP: COMPRESS ZSTD can cause excessive memory usage. An attacker that has valid credentials can select a compression algorithm for the IMAP connection whose decompressio
n state requires a large amount of memory, and open several such connections.
Risk:
The memory limit of the process is reached with only a few connections, terminating the process and all connections it handles, which can cause degradation or denial of s
ervice for IMAP. No publicly available exploits are known.
Solution:
Disable IMAP compression. Alternatively limit the number of connections handled by a single imap-login process, though this has a performance impact. Update to non-vulner
able version.
1
0
Hi!
We are happy to publish version 2.4.5 of Dovecot and Pigeonhole. These contain CVEs, discovered by external researches. The majority of these have been discovered with help of automated code analysis tools like claude code security, which is why some of these are rather old, missed bugs.
Distributions have changed
- Jammy (Ubuntu 22.04) is no longer provided in repo.dovecot.org
- Resolute Raccoon (Ubuntu 26.04) has been added to repo.dovecot.org
No new dependencies have been added.
Note that there are experimental features in 2.4, one is enabled with `--enable-experimental-mail-utf8`, and another with `--enable-experimental-imap4rev2`, and you also need to set mail_utf8_extensions=yes and imap4rev2_enabled=yes to enable them in config.
https://dovecot.org/releases/2.4/dovecot-2.4.5.tar.gz
https://dovecot.org/releases/2.4/dovecot-2.4.5.tar.gz.sig
https://pigeonhole.dovecot.org/releases/2.4/dovecot-pigeonhole-2.4.5.tar.gz
https://pigeonhole.dovecot.org/releases/2.4/dovecot-pigeonhole-2.4.5.tar.gz…
Binary packages in https://repo.dovecot.org/
Docker images in https://hub.docker.com/r/dovecot/dovecot
---
* CVE-2026-27852: Messages with a huge number of From/To/Cc/etc email addresses
could result in excessive memory usage.
* CVE-2026-33263: Submission: Login service crashes with panic once
mail_max_userip_connections limit is reached.
* CVE-2026-33604: The SMTP outbound dot-stuffing mechanism does not properly
escape dots following a bare \r in message bodies, potentially allowing
spoofed emails via malicious end-of-DATA injection.
* CVE-2026-33606: Mail content stored by a user can be crafted so that it is
interpreted as dsync protocol commands when an administrator later runs dsync
with the stream protocol, for example during a migration.
* CVE-2026-33607: IMAP LIST command could be used to cause excessive CPU usage.
* CVE-2026-40014: IMAP THREAD command could have used excessive amount of CPU
processing a single email with a massive number of Message-IDs in References
header.
* CVE-2026-40015: Invalid IMAP command sent to imap-hibernate process might
crash it.
* CVE-2026-40017: IMAP THREAD command could have used excessive amount of CPU
processing emails with a large number of specially crafted Message-IDs in
References header. The fix requires a new dovecot.index.thread file format,
which is enabled only after setting dovecot_storage_version or newer. This
rebuilds the index, so it will cause some extra CPU usage and extra
metacache disk IO usage. It shouldn't cause (much) extra object storage IO,
because all the fields should be coming from dovecot.index.cache.
* CVE-2026-40203: When IMAP COMPRESS=DEFLATE was enabled, an attacker
could send mails into a victim's mailbox and observe network traffic to
determine whether a secret message matched a known string by comparing
compressed response sizes (a CRIME-style attack). The fix resets the
compression dictionary after each IMAP command, preventing information from
leaking between commands.
* CVE-2026-40205: If multiple OAUTH scopes were required, then
this could have been only partially enforced with certain
configurations.
* CVE-2026-4200: XCLIENT FORWARD allows to forward key only passdb
fields without the "forward_" prefix which allows connections from
trusted networks to set nopasswd field which allows to skip the
authentication.
* CVE-2026-42391: Pre-login IMAP ID command could have used excessive
amount of memory, causing the process to become killed and disconnecting
all the other IMAP connections being proxied by the process. Or
alternatively it could have caused excessive CPU usage, slowing down
all the other IMAP connections being proxied by the process.
* CVE-2026-42392: If URLAUTH is enabled, sending an invalid IMAP URLFETCH
can result in an untagged NO response containing uninitialized memory,
potentially leaking sensitive data.
* CVE-2026-42393: Doveadm password length or API key length could still
be determined via timing based attacks.
* CVE-2026-42395: XCLIENT FORWARD command from login_trusted_networks
could have been used to cause login processes to crash.
* CVE-2026-52681: Sieve resource usage (sieve_max_cpu_time) was tracked
in the active Sieve binary. Switching to a different active binary
could have been used to reset (bypass) the resource usage.
* CVE-2026-52687: Using IMAP COMPRESS ZSTD command can cause excessive
memory usage in imap-login process, possibly making it reach vsz_limit
and kill all the connections being served by the process. Fixed by
disabling COMPRESS command with all other compression algorithms than
the standard DEFLATE.
* CVE-2026-73208: In oauth2, scope/aud checking was done with JWT tokens.
Now it requires all scopes.
* CVE-2026-73209: Sending IMAP COMPRESS package containing zero-length
frames crashes imap or imap-login process.
* auth: SIGHUP no longer flushes the passdb cache and SIGUSR2 no longer
logs cache statistics. Use "doveadm auth cache flush" and the new
"doveadm auth cache status" instead.
* auth: The OTP authentication mechanism, the {OTP} password scheme and
the passdb set-credentials support have been removed. They were
unmaintained and unused. This also drops the passdb_sql_update_query
setting.
* config: doveconf no longer prints a flat global setting when a
top-level named filter overrides the same setting.
* doveadm: The doveadm protocol has been bumped to v1.4. The server uses
the newer multiplex stream format with clients supporting it. Older
clients keep working unchanged.
* imap: Change imap_compress_on_proxy default to yes.
* lib-dict-extra: Increase dict client request timeout from 30s to 65s,
so it stays above the SQL/Cassandra query timeout.
* lib-http: HTTP requests are now parsed strictly: obsolete line folding
(obs-fold) and a bare LF line terminator are rejected. Both are
request desynchronization/smuggling risks. HTTP responses are still
parsed leniently.
* lib-storage: A '~' in a mailbox name is now escaped only when it is at
the beginning of the mailbox name, not at the beginning of every
hierarchy part. Directories written by older versions are migrated
automatically while listing mailboxes.
* lib-var-expand: Add %{time:unix} provider and the epoch, from_epoch,
date, iso8601 and escape filters. Deprecates the old time providers.
* lib-var-expand: The safe filter must now be the last filter in the
chain.
* master: Increase the timeout after config reload before killing still
running old processes from 6s to 35s, so that lib-master can stop them
gracefully first.
+ config: Support heredoc syntax for multi-line setting values:
key = <<EOD ... EOD. doveconf now outputs inline SET_FILE contents
(e.g. ssl_ca) using heredoc instead of the "inline:" prefix. The
"inline:" form is still accepted.
+ configure: Build imap-hibernate also when only kqueue notify is
available.
+ doveadm: Add "doveadm auth cache status" command, with --reset for
clearing the counters.
+ doveadm: dump - List all supported dump types, and print the key type
also for KEM and unsupported keys.
+ fts-flatcurve: Add support for phrase searching. This fixes false
positives where the searched words existed, but not as a phrase.
+ fts-flatcurve: Delete the FTS index directory also when a Maildir
mailbox is deleted.
+ imap: Add [THROTTLED] response code to tagged replies when a plugin
has throttled the command.
+ last-login: Add last_login_dict_fields setting for updating multiple
dictionary fields at login.
+ lib-dcrypt: Add ML-KEM-512/768/1024 support with OpenSSL 3.
+ lib-dcrypt: Support AEAD with Dovecot key encryption.
+ lib-settings: Expand %{variables} also in strlist and boollist keys.
+ lib-sql: sqlite - Add sqlite_busy_timeout setting, default 1s.
+ login-common: Log the destination also when a proxy connection fails.
+ quota: Update quota-clone also when "doveadm quota recalc" is run.
- Fix building on systems with a signed 32-bit time_t.
- Fix building with Lua when LUA_LIBS contains linker flags such as -L.
- anvil: Fix busy loop eating CPU after an admin socket connection was
disconnected.
- auth: Fix authentication failing after a password change when the
passdb cache entry was verified by an auth worker.
- auth: Fix the credentials scheme of one passdb leaking into the next
one during a multi-passdb lookup.
- auth: oauth2 - Fix losing userdb_* fields during OAUTHBEARER
authentication.
- auth: passwd-file - Fix %{passdb:...} and %{userdb:...} expansion
returning garbage or crashing.
- config: Fix crash in "doveconf -f" for a filter that includes a @group.
- config: Fix crash when including a default @group into a filter.
- config: Fix hiding secrets in doveconf output.
- config: Fix startup failures with some settings containing %{variables}.
- configure: Fix BUILD_IMAP_HIBERNATE detection.
- doc: solr-schema-9.xml - Add the mandatory tokenizer class attribute.
- doveadm: compress-connect - Fix writing server input to a non-blocking
stdout.
- doveadm: fs delete - Fix crash with concurrent async deletes.
- doveconf: Fix bogus "Multiple settings matched" error when stdout is
redirected to a file that already has content.
- dsync: Fix truncating a mailbox attribute value when it is compared to
the local one, e.g. truncating a Sieve script.
- dsync: backup - Mailbox attributes changed or created only in the
destination are now reverted or deleted.
- fts-flatcurve: Ignore index directory entries that vanish during
iteration.
- fts: Don't run FTS optimize on forced resync.
- fts: build-mail - Fix accessing Content-Type header buffer out of
bounds.
- imap-login, pop3-login: Tolerate SASL continuations "+" without a
trailing space when proxying authentication.
- imap: Don't report FETCH output stream errors as
"BUG: Unknown internal error".
- imap: Fix hibernation always failing on FreeBSD.
- imap: Fix panic on GETMETADATA with an invalid UTF-8 mailbox pattern.
- imapc: Don't send SEEEN/UNSEEN to the remote server when private
indexes are used.
- imapc: Fix SEARCH results pointing at wrong messages after an untagged
EXPUNGE.
- imapc: Fix SORT returning an empty result when search criteria were
used.
- imapc: Fix crash when copying a mail that was already expunged in the
source mailbox.
- imapc: Fix stale SEARCH/SORT results after a STORE in the same
session.
- imapc: Honor imapc_features=no-search also for SORT.
- imapc: Properly handle search criteria that can be sent to remote server.
- lib-dcrypt: Don't panic on key algorithms the backend doesn't support.
- lib-dcrypt: Fix x9.62 ECDSA signatures randomly failing verification.
- lib-dict-backend: cdb - Fix use-after-free of the returned key.
- lib-dns-client: Fix handling of a disconnect initiated by the
dns-client service.
- lib-fs: Fix panic in fs_write_stream_abort(), e.g. when the disk is
full during FTS indexing.
- lib-index: Fix "File is already open" error when appending to the
transaction log while another process is rotating it. This showed up
as "NO [SERVERBUG] Internal error occurred." without any logging.
- lib-ldap: Fall back to system default CA paths, needed for OpenLDAP
built against GnuTLS.
- lib-mail: istream-binary-converter - Fix heap use-after-free with a
bodyless MIME part.
- lib-mail: message-parser - Fix out of bounds read with an empty
preamble, fix skipping the epilogue boundary line, and degrade to a
re-parse instead of panicking with an inconsistent cached MIME tree.
- lib-master: Fix kick reason when the KICK-USER-SIGNAL command arrives
late, which logged "Killed with signal 15" instead of "User kicked".
- lib-oauth2: jwt - Fix use-after-realloc, guard against an empty body
segment and percent-encode bare "." and ".." identifiers.
- lib-program-client: Fix panic upon irregular termination.
- lib-settings: Fix sorting of the settings history, which caused
changed defaults and renames to be ignored once a plugin registered
its own history, if dovecot_config_version has been set to greater
than 2.4.0.
- lib-smtp: Fix assert with an empty broken localpart.
- lib-smtp: xclient - Reject an invalid HELO parameter with 501.
- lib-sql: pgsql - Fix binary field values for rows after the first.
This mainly affected dict-sql maps with hexblob fields.
- lib-ssl-iostream: Fix crash at process exit with OpenSSL 4.0.
- lib-storage: Don't log an error when the client resets the connection
while saving a mail.
- lib-storage: Fix crash when reverting a failed mailbox deletion.
- lib-storage: Fix decoded size calculation for base64 attachments,
which could delete the cache record of a mail with a detached
attachment.
- lib-storage: Fix handling escaped mailbox names in the mailbox list
index.
- lib-storage: Fix rewriting non-NFC subscriptions with mUTF-7 storage
names, which caused repeated rename errors.
- lib-storage: Fix searching flags when the view is not up to date. This
broke e.g. a pipelined UID STORE +FLAGS \Deleted followed by UID
EXPUNGE.
- lib-storage: Fix the mailbox vsize header not being repaired when it
is corrupted, causing wrong mailbox sizes to be reported.
- lib-storage: thread - Fix panic when running IMAP THREAD in multiple
connections in parallel.
- lib-var-expand: Reject an empty separator in the index filter, which
caused an infinite loop.
- lib: Fix crash and out of bounds reads when decoding IDN addresses.
Reachable only with the experimental mail UTF-8 support enabled.
- lib: ioloop - Fix panic and delayed timeouts when time moves forwards.
- lib: ostream-multiplex - Fix stalls, busy loops and a panic when
streaming data through a multiplexed connection, e.g. IMAP FETCH
through a login proxy or TLS connections.
- login-common: Fix connection hanging if an ostream write failed. This
happened at least with HAProxy health check connections.
- login-common: Fix real_remote_ip being looked up incorrectly.
- login-common: Reject proxy credentials with ASCII control characters.
- login-proxy: Fix "doveadm kick" for proxied connections in
high-security mode, and log "Kicked by admin" as the reason.
- maildir: Fix random SEARCH failures when another session concurrently
expunges mails.
- quota: Fix maildir quota dropping to zero after IMAP MOVE or REPLACE.
- submission-login: proxy - Fix crash and unbounded memory usage with a
multi-line or malformed AUTH reply from the backend.
---
* CVE-2026-33605: managesieve-login: Pre-auth crash. An unauthenticated attacker
can crash the ManageSieve login process by sending a small malformed command
before authenticating.
* CVE-2026-40019: v2.4.3 regression: managesieve-login pre-auth infinite loop.
An unauthenticated attacker can send a truncated quoted argument to the
ManageSieve login process, which makes it spin in an infinite loop consuming CPU.
* CVE-2026-42007: sieve-editheader: An attacker that has valid credentials can
use a Sieve script with the editheader extension to trigger a use-after-free
in the mail editing code, and to write memory contents beyond the intended
buffer in the delivered mail.
* lib-sieve: sieve_max_cpu_time now defaults to 30s globally, so the
limit also applies to MDA delivery. Previously the global default was
unlimited and only imap_sieve used 30s. The old defaults are kept for
older dovecot_config_version values.
* lib-sieve: enotify - The number of notify actions performed during a
single script execution is now limited to 10 by default. See the new
sieve_notify_max_notifications setting.
* lib-sieve: enotify - A single "mailto:" notify action is now limited
to 8 recipients and 16 additional headers by default. See the new
sieve_notify_mailto_max_recipients and sieve_notify_mailto_max_headers
settings.
* imap-filter-sieve: FILTER SIEVE SCRIPT literals larger than
sieve_max_script_size are now rejected before the script is read.
- lib-sieve: Fix stack overflow occurring when a script requires the
same extension repeatedly.
- lib-sieve: encoded-character - Fix integer overflow parsing
${unicode:...} values with 9 or more hex digits.
- lib-sieve: variables - Fix integer overflow parsing numeric variable
index.
- lib-sieve: regex - Fix panic occurring when more than 8 group values
are matched.
- lib-sieve: ldap - Fix LDAP settings missing from the LDAP storage
plugin.
- managesieve-login: Fix capability reporting when Sieve settings use
%variables.
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