Bug 1912455 (CVE-2020-24386)

Summary:	CVE-2020-24386 dovecot: IMAP hibernation function allows mail access
Product:	[Other] Security Response	Reporter:	Pedro Sampaio <psampaio>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	anon.amish, bennie.joubert, djez, janfrode, mhlavink, tcullum
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	dovecot 2.3.13	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-05-18 20:38:01 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:	1912456, 1913534, 1913535
Bug Blocks:	1912462

Description Pedro Sampaio 2021-01-04 14:36:44 UTC

A flaw was found in dovecot before version 2.3.13. 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.

References:

https://www.openwall.com/lists/oss-security/2021/01/04/4
https://dovecot.org/pipermail/dovecot-news/2021-January/000448.html

Comment 1 Pedro Sampaio 2021-01-04 14:37:16 UTC

Created dovecot tracking bugs for this issue:

Affects: fedora-all [bug 1912456]

Comment 3 Todd Cullum 2021-01-08 00:39:30 UTC

Mitigation:

To mitigate this flaw, ensure that imap_hibernate_timeout is set to 0 or not set at all/commented out in both /etc/dovecot/dovecot.conf or /etc/dovecot/conf.d/20-imap.conf.

Comment 4 Todd Cullum 2021-01-08 00:47:33 UTC

Upstream commit: https://github.com/dovecot/core/commit/62061e8cf68f506c0ccaaba21fd4174764ca875f

Comment 5 Todd Cullum 2021-01-08 01:16:02 UTC

External References:

https://dovecot.org/pipermail/dovecot-news/2021-January/000448.html

Comment 9 errata-xmlrpc 2021-05-18 15:51:47 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:1887 https://access.redhat.com/errata/RHSA-2021:1887

Comment 10 Product Security DevOps Team 2021-05-18 20:38:01 UTC

This bug is now closed. Further updates for individual products will be reflected on the CVE page(s):

https://access.redhat.com/security/cve/cve-2020-24386