CVE-2020-24386: IMAP hibernation allows accessing other peoples mail

[Marc Roos]

 This also applies when you have users seperated at os level?


-----Original Message-----
Sent: 04 January 2021 13:03
To: dovecot-news at dovecot.org; dovecot at dovecot.org
Subject: CVE-2020-24386: IMAP hibernation allows accessing other peoples 
mail

Open-Xchange Security Advisory 2021-01-04

Product: Dovecot
Vendor: OX Software GmbH
Internal reference: DOP-2009 (Bug ID)
Vulnerability type: CWE-150: Improper Neutralization of Escape, Meta, or 
Control Sequences Vulnerable version: 2.2.26-2.3.11.3 Vulnerable 
component: imap Report confidence: Confirmed Solution status: Fixed by 
Vendor Fixed version: 2.3.13 Vendor notification: 2020-08-17 Solution 
date: 2020-08-27 Public disclosure: 2021-01-04 CVE reference: 
CVE-2020-24386
CVSS: 8.2 (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:C/C:H/I:H/A:N)

Vulnerability Details:

When imap hibernation is active, an attacker can cause Dovecot to 
discover file system directory structure and access other users' emails 
using specially crafted command. The attacker must have valid 
credentials to access the mail server.

Risk:

Attacker can access other users' emails and filesystem information.

Workaround:

Operators can choose to disable IMAP hibernation. IMAP hibernation is 
not on by default. To ensure imap hibernation is disabled, make sure 
imap_hibernate_timeout is set to 0 or unset.

Solution:

Operators should update to 2.3.13 or later version.