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: vulnerabilityAssignee: Red Hat Product Security <security-response-team>
Status: CLOSED ERRATA QA Contact:
Severity: medium Docs Contact:
Priority: medium    
Version: unspecifiedCC: 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:
Embargoed:
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