Bug 1900826 (CVE-2020-28896)

Summary:	CVE-2020-28896 mutt: Incorrect handling of invalid initial IMAP responses could lead to an authentication attempt over unencrypted connection
Product:	[Other] Security Response	Reporter:	Guilherme de Almeida Suckevicz <gsuckevi>
Component:	vulnerability	Assignee:	Red Hat Product Security <security-response-team>
Status:	CLOSED ERRATA	QA Contact:
Severity:	medium	Docs Contact:
Priority:	medium
Version:	unspecified	CC:	athoscribeiro, dakingun, databases-maint, hhorak, jmmahler, me, mmuzila, pkubat
Target Milestone:	---	Keywords:	Security
Target Release:	---
Hardware:	All
OS:	Linux
Whiteboard:
Fixed In Version:	mutt 2.0.2	Doc Type:	If docs needed, set a value
Doc Text:		Story Points:	---
Clone Of:		Environment:
Last Closed:	2021-11-02 17:59:38 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Bug Depends On:	1900827, 1901316, 1910624
Bug Blocks:	1900828

Description Guilherme de Almeida Suckevicz 2020-11-23 19:37:24 UTC

Mutt had incorrect error handling when initially connecting to an IMAP server, which could result in an attempt to authenticate without enabling TLS.

References:
http://lists.mutt.org/pipermail/mutt-announce/Week-of-Mon-20201116/000031.html
https://mailman.neomutt.org/pipermail/neomutt-users-neomutt.org/2020-November/000929.html

Upstream patchs:
https://gitlab.com/muttmua/mutt/-/commit/04b06aaa3e0cc0022b9b01dbca2863756ebbf59a
https://github.com/neomutt/neomutt/commit/9c36717a3e2af1f2c1b7242035455ec8112b4b06

Comment 1 Guilherme de Almeida Suckevicz 2020-11-23 19:37:41 UTC

Created mutt tracking bugs for this issue:

Affects: fedora-all [bug 1900827]

Comment 3 Todd Cullum 2020-11-24 20:24:51 UTC

Statement:

Red Hat Product Security has rated the severity of this flaw as Moderate because although the Confidentiality impact is high, the attack complexity is also high as a particular attacker would at least need to coordinate social engineering a victim to connect to a bad server, and also perform a man-in-the-middle attack or perform similar interception of the connection. Please see the following page for details on Red Hat severity ratings with special attention to Moderate: https://access.redhat.com/security/updates/classification .

Comment 6 errata-xmlrpc 2021-11-09 17:36:44 UTC

This issue has been addressed in the following products:

  Red Hat Enterprise Linux 8

Via RHSA-2021:4181 https://access.redhat.com/errata/RHSA-2021:4181