- dovecot - dovecot.org

Replication: Mails deleted over POP3 aren't deleted at the same time from the second server
by Lukas 12 Aug '20

12 Aug '20

Hi, I have two Dovecot 2.3.8 (on RHEL 8.2) servers. Replication works great except in one situation. What works: * If one server receives an email, it is immediately available on the other server. * If an email is deleted via IMAP from one server, it is immediately deleted from the other server. What doesn't work: If a user retrieves (download + delete) an email via POP3 (Thunderbird), then the mail is only deleted from the server from which it was downloaded but not from the other server. The email is only deleted from the other server in the following situations: * If a new email arrives (triggers a sync action) * When the next full sync happens (I temporarily set replication_full_sync_interval to "1 hour") * When forcing a manual full sync (doveadm replicator replicate user_name) If I activate debug logging (mail_debug = yes), I can immediately see a replication action when an email is deleted via IMAP. However, when an email is deleted via POP3, nothing is logged (because no replication happens). Does anyone have an idea why deleting an email via POP3 isn't replicated and how to configure this? Thanks for your help. Lukas My config (it is identical on on both servers, except of the "mail_replica" and "address" parameters): auth_mechanisms = plain login auth_username_format = %n doveadm_password = # hidden, use -P to show it doveadm_port = 12345 login_log_format_elements = user=<%u> method=%m rip=%r lip=%l mpid=%e %c %k mail_gid = vmail mail_home = /var/spool/dovecot/%u mail_location = sdbox:/var/spool/dovecot/%u mail_plugins = " notify replication" mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = mailbox Drafts { auto = subscribe special_use = \Drafts } mailbox Sent { auto = subscribe special_use = \Sent } mailbox Spam { auto = subscribe } mailbox Trash { auto = subscribe special_use = \Trash } prefix = } passdb { args = /etc/dovecot/deny.%s deny = yes driver = passwd-file } passdb { args = scheme=SSHA512 username_format=%n /etc/dovecot/passwd driver = passwd-file } plugin { mail_replica = tcps:server2.example.com:12345 sieve = ~/sieve/.dovecot.sieve } protocols = imap pop3 lmtp sieve replication_full_sync_interval = 1 hours service aggregator { fifo_listener replication-notify-fifo { user = vmail } unix_listener replication-notify { user = vmail } } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0660 user = postfix } unix_listener auth-userdb { mode = 0600 user = vmail } user = $default_internal_user } service doveadm { inet_listener { address = ... port = 12345 ssl = yes } user = vmail } service imap-login { inet_listener imap { port = 0 } inet_listener imaps { address = ... port = 993 } } service lmtp { unix_listener /var/spool/postfix/private/dovecot-lmtp { group = postfix mode = 0600 user = postfix } } service managesieve-login { inet_listener sieve { address = ... port = 4190 } } service pop3-login { inet_listener pop3 { port = 0 } inet_listener pop3s { address = ... port = 995 } } service replicator { process_min_avail = 1 unix_listener replicator-doveadm { mode = 0600 user = vmail } } ssl = required ssl_cert = </etc/letsencrypt/live/server1.example.com/fullchain.pem ssl_client_ca_file = /etc/pki/tls/cert.pem ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it ssl_min_protocol = TLSv1.2 ssl_options = no_compression syslog_facility = local5 userdb { args = username_format=%n /etc/dovecot/passwd driver = passwd-file result_failure = return-fail result_internalfail = return-fail } protocol sieve { ssl = required } protocol lmtp { mail_plugins = " notify replication sieve" }

1 0

auth debug log entry incorrect
by Tomas Habarta 12 Aug '20

12 Aug '20

Hello, just want to report a slightly confusing log entry on auth-debug level I have encountered while setting up Kerberos auth. Users are stored in ldap, Kerberos makes use of the same ldap as its backend, goal was to enable users to use their principals in addition to simple login with mailAddress/userPassword combination. Sample entry relevant attrs: --- mailAddress: sn.gn(a)example.com mailDeliveryAddress: 123456(a)example.com uid: u123456 krbPrincipalName: u123456@REALM krbPrincipalName: user123456@REALM krbPrincipalName: alias@REALM --- with pass_attrs = =user=%{ldap:mailDeliveryAddress},=password=%{ldap:userPassword},=k5principals=%{ldap:krbPrincipalName} I can see incorrectly logged ldap search result for krbPrincipalName attr as it is written 3 times with the same value -- number is correct, values should differ. All is working ok as expected, but was a bit confusing while tuning /etc/krb5.conf on non-working remote client whilst local client had no issues (mutt). Anyway, to eventually save someone's time, this seems to be easy enough to be fixed. Thanks for this great software, Tomas dovecot[13337]: auth: Debug: ldap(sn.gn(a)example.com,10.0.9.14,<6xHsI62sJoWT+2C4>): result: mailDeliveryAddress=123456(a)example.com krbPrincipalName=u123456@REALM,u123456@REALM,u123456@REALM; krbPrincipalName,mailDeliveryAddress unused dovecot[13337]: auth: Debug: ldap(sn.gn(a)example.com,10.0.9.14,<6xHsI62sJoWT+2C4>): username changed sn.gn(a)example.com -> 123456(a)example.com dovecot[13337]: auth: Warning: ldap(123456(a)example.com,10.0.9.14,<6xHsI62sJoWT+2C4>): Multiple values found for 'krbPrincipalName', using value 'u123456@REALM' dovecot[13337]: auth: Debug: ldap(123456(a)example.com,10.0.9.14,<6xHsI62sJoWT+2C4>): Finished passdb lookup dovecot[13337]: auth: Debug: gssapi(123456(a)example.com,10.0.9.14,<6xHsI62sJoWT+2C4>): authorized by k5principals field: u123456@REALM dovecot[13337]: auth: Debug: auth(123456(a)example.com,10.0.9.14,<6xHsI62sJoWT+2C4>): Auth request finished dovecot[13337]: auth: Debug: client passdb out: OK 1 user=123456(a)example.com k5principals=u123456@REALM original_user=u123456@REALM dovecot[13337]: auth: Debug: master in: REQUEST 3251372033 13340 1 3bbd5f6931fe4e949e7822657da9e33b session_pid=13343 request_auth_token # 2.3.8 (9df20d2db): /etc/dovecot/dovecot.conf # Pigeonhole version 0.5.8 (b7b03ba2) # OS: Linux 4.18.0-193.14.2.el8_2.x86_64 x86_64 CentOS Linux release 8.2.2004 (Core)

1 0

CVE-2020-12674: Specially crafted RPA authentication message crashes auth
by Aki Tuomi 12 Aug '20

12 Aug '20

Open-Xchange Security Advisory 2020-08-12 Affected product: Dovecot IMAP server Internal reference: DOP-1869 (Bug ID) Vulnerability type: CWE-126 (Buffer over-read) Vulnerable version: 2.2 Vulnerable component: auth Fixed version: 2.3.11.3 Report confidence: Confirmed Solution status: Fix available Vendor notification: 2020-05-03 Researcher credit: Orange from DEVCORE team CVE reference: CVE-2020-12674 CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) Vulnerability Details: Dovecot's RPA mechanism implementation accepts zero-length message, which leads to assert-crash later on Risk: An adversary can use this vulnerability to crash dovecot auth process repeatedly, preventing login. Steps to reproduce: (echo 'AUTH RPA'; echo -ne '\x60\x11\x06\x09\x60\x86\x48\x01\x86\xf8\x73\x01\x01\x01\x00\x04\x00\x00\x01' | base64 -w 0; echo ; echo -ne '\x60\x11\x06\x09\x60\x86\x48\x01\x86\xf8\x73\x01\x01\x00\x03A@A\x00' | base64 -w 0; echo ; echo QUIT) | nc 127.0.0.1 110 Workaround: Disable RPA authentication. Solution: Upgrade to fixed version. Best regards, Aki Tuomi Open-Xchange oy

1 0

CVE-2020-12673: Specially crafted NTML package can crash auth service
by Aki Tuomi 12 Aug '20

12 Aug '20

Open-Xchange Security Advisory 2020-08-12 Affected product: Dovecot IMAP server Internal reference: DOP-1870 (Bug ID) Vulnerability type: CWE-789 (Uncontrolled Memory Allocation) Vulnerable version: 2.2 Vulnerable component: auth Fixed version: 2.3.11.3 Report confidence: Confirmed Solution status: Fix available Vendor notification: 2020-05-03 CVE reference: CVE-2020-12673 CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) Vulnerability Details: Dovecot's NTLM implementation does not correctly check message buffer size, which leads to reading past allocation which can lead to crash. Risk: An adversary can use this vulnerability to crash dovecot auth process repeatedly, preventing login. Steps to reproduce: (echo 'AUTH NTLM'; echo -ne 'NTLMSSP\x00\x01\x00\x00\x00\x00\x02\x00\x00AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA' | \ base64 -w0 ;echo ;echo -ne 'NTLMSSP\x00\x03\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00AA\x00\x00\x41\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00orange\x00'| \ base64 -w0;echo ; echo QUIT) | nc 127.0.0.1 110 Workaround: Disable NTLM authentication. Solution: Upgrade to fixed version. Best regards, Aki Tuomi Open-Xchange oy

1 0

CVE-2020-12100: Receiving mail with deeply nested MIME parts leads to resource exhaustion.
by Aki Tuomi 12 Aug '20

12 Aug '20

Open-Xchange Security Advisory 2020-08-12 Affected product: Dovecot IMAP server Internal reference: DOP-1849 (Bug ID) Vulnerability type: Uncontrolled recursion (CWE-674) Vulnerable version: 2.0 Vulnerable component: submission, lmtp, lda Fixed version: 2.3.11.3 Report confidence: Confirmed Solution status: Fix available Vendor notification: 2020-04-23 CVE reference: CVE-2020-12100 CVSS: 7.5 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H) Vulnerability Details: Receiving mail with deeply nested MIME parts leads to resource exhaustion as Dovecot attempts to parse it. Risk: Malicious actor can cause denial of service to mail delivery by repeatedly sending mails with bad content. Workaround: Limit MIME structures in MTA. Solution: Upgrade to fixed version. Best regards, Aki Tuomi Open-Xchange oy

1 0

Dovecot v2.3.11.3 released
by Aki Tuomi 12 Aug '20

12 Aug '20

We are pleased to release v2.3.11.3. Please find it from locations below: https://dovecot.org/releases/2.3/dovecot-2.3.11.3.tar.gz https://dovecot.org/releases/2.3/dovecot-2.3.11.3.tar.gz.sig Binary packages in https://repo.dovecot.org/ Docker images in https://hub.docker.com/r/dovecot/dovecot Aki Tuomi Open-Xchange oy --- * CVE-2020-12100: Parsing mails with a large number of MIME parts could have resulted in excessive CPU usage or a crash due to running out of stack memory. * CVE-2020-12673: Dovecot's NTLM implementation does not correctly check message buffer size, which leads to reading past allocation which can lead to crash. * CVE-2020-10967: lmtp/submission: Issuing the RCPT command with an address that has the empty quoted string as local-part causes the lmtp service to crash. * CVE-2020-12674: Dovecot's RPA mechanism implementation accepts zero-length message, which leads to assert-crash later on. * Events: Fix inconsistency in events. See event documentation in https://doc.dovecot.org. * imap_command_finished event's cmd_name field now contains "unknown" for unknown commands. A new "cmd_input_name" field contains the command name exactly as it was sent. * lib-index: Renamed mail_cache_compress_* settings to mail_cache_purge_*. Note that these settings are mainly intended for testing and usually shouldn't be changed. * events: Renamed "index" event category to "mail-index". * events: service:<name> category is now using the name from configuration file. * dns-client: service dns_client was renamed to dns-client. * log: Prefixes generally use the service name from configuration file. For example dict-async service will now use "dict-async(pid): " log prefix instead of "dict(pid): " * *-login: Changed logging done by proxying to use a consistent prefix containing the IP address and port. * *-login: Changed disconnection log messages to be slightly clearer. + dict: Add events for dictionaries. + lib-index: Finish logging with events. + oauth2: Support local validation of JWT tokens. + stats: Add support for dynamic histograms and grouping. See https://doc.dovecot.org/configuration_manual/stats/. + imap: Implement RFC 8514: IMAP SAVEDATE + lib-index: If a long-running transaction (e.g. SORT/FETCH on a huge folder) adds a lot of data to dovecot.index.cache file, commit those changes periodically to make them visible to other concurrent sessions as well. + stats: Add OpenMetrics exporter for statistics. See https://doc.dovecot.org/configuration_manual/stats/openmetrics/. + stats: Support disabling stats-writer socket by setting stats_writer_socket_path="". - auth-worker: Process keeps slowly increasing its memory usage and eventually dies with "out of memory" due to reaching vsz_limit. - auth: Prevent potential timing attacks in authentication secret comparisons: OAUTH2 JWT-token HMAC, imap-urlauth token, crypt() result. - auth: Several auth-mechanisms allowed input to be truncated by NUL which can potentially lead to unintentional issues or even successful logins which should have failed. - auth: When auth policy returned a delay, auth_request_finished event had policy_result=ok field instead of policy_result=delayed. - auth: auth process crash when auth_policy_server_url is set to an invalid URL. - auth: Lua passdb/userdb leaks stack elements per call, eventually causing the stack to become too deep and crashing the auth or auth-worker process. - dict-ldap: Crash occurs if var_expand template expansion fails. - dict: If dict client disconnected while iteration was still running, dict process could have started using 100% CPU, although it was still handling clients. - doveadm: Running doveadm commands via proxying may hang, especially when doveadm is printing a lot of output. - imap: "MOVE * destfolder" goes to a loop copying the last mail to the destination until the imap process dies due to running out of memory. - imap: Running "UID MOVE 1:* Trash" on an empty folder goes to infinite loop. - imap: SEARCH doesn't support $. - lib-compress: Buffer over-read in zlib stream read. - lib-dns: If DNS lookup times out, lib-dns can cause crash in calling process. - lib-index: Fixed several bugs in dovecot.index.cache handling that could have caused cached data to be lost. - lib-index: Writing to >=1 GB dovecot.index.cache files may cause assert-crashes: Panic: file mail-index-util.c: line 37 (mail_index_uint32_to_offset): assertion failed: (offset < 0x40000000) - lib-mail: v2.3.11 regression: MIME parts not returned correctly by Dovecot MIME parser. - lib-ssl-iostream: Fix buggy OpenSSL error handling without assert-crashing. If there is no error available, log it as an error instead of crashing: Panic: file iostream-openssl.c: line 599 (openssl_iostream_handle_error): assertion failed: (errno != 0) - lib-ssl-iostream: ssl_key_password setting did not work. - pop3-login: Login didn't handle commands in multiple IP packets properly. This mainly affected large XCLIENT commands or a large SASL initial response parameter in the AUTH command. - pop3: pop3_deleted_flag setting was broken, causing: Panic: file seq-range-array.c: line 472 (seq_range_array_invert): assertion failed: (range[count-1].seq2 <= max_seq) - pop3-login: Login would fail with "Input buffer full" if the initial response for SASL was too long. - submission: A segfault crash may occur when the client or server disconnects while a non-transaction command like NOOP or VRFY is still being processed. - virtual: Copying/moving mails with IMAP into a virtual folder assert-crashes: Panic: file cmd-copy.c: line 152 (fetch_and_copy): assertion failed: (copy_ctx->copy_count == seq_range_count(&copy_ctx->saved_uids))

1 0

Client shows incorrect message counts
by Antonio Leding 11 Aug '20

11 Aug '20

Hello all… First, a disclaimer…I am aware that this is very likely not a Dovecot related issue but I am truly pulling whatever hair I have left out of my head and given the brain-power of this mailer, I thought someone might know what is going in here. The issues is this… I check the message counts for a given account using doveadm and get a given number. I then configure the same account in 3 mail clients: Apple Mail, Mailmate, and Thunderbird. Both the Mailmate and Thunderbird message counts match exactly with the doveadm numbers. Apple Mail is low in almost all cases. I have tried every idea I have found including: — Delete and recreate the mail account — Rebuild mailbox — Resync mailbox — Reindex Spotlight — Removing the "~/Library/Mail/V*/Envelope*” files; restart Mail — Remove the entire "~/Library/Mail/V*” directory; restart Mail So, at wit’s end and again, apologies for this not being a Dovecot-centric issue but I know you are all on top of this stuff and may have an idea… Thanks in advance...

2 7

Thanks, got replys
by Chris Bennett 11 Aug '20

11 Aug '20

I've got a mix of some receive only, some send only. I tried to slam together two different configs really fast. This helped. I'll look things over and post some configs after a bit. Thanks again! Chris Bennett

1 0

Test on sending only
by Chris Bennett 10 Aug '20

10 Aug '20

I had to move off of a server to this one too fast. Having problems If this goes through, if someone could reply to chris(a)bennettconstruction.us instead of on-list. Thanks, Chris Bennett

1 0

IMAP Permissions per IP
by Jorge Bastos 10 Aug '20

10 Aug '20

Howdy, Is it possible to define IMAP permissions per IT? What i would like to do is: * IP 1.1.1.1 IS THE ONLY ONE that has permission for EXPUNGE Is it possible? Thanks in advanced,

2 1