Medium severity · published Nov 23, 2020
CVE-2020-28896
Mutt before 2.0.2 and NeoMutt before 2020-11-20 did not ensure that $ssl_force_tls was processed if an IMAP server's initial server response was invalid
5.3
CVSS
2.4%
EPSS
No
On KEV
Description
Mutt before 2.0.2 and NeoMutt before 2020-11-20 did not ensure that $ssl_force_tls was processed if an IMAP server's initial server response was invalid. The connection was not properly closed, and the code could continue attempting to authenticate. This could result in authentication credentials being exposed on an unencrypted connection, or to a machine-in-the-middle.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)2.4% · higher than 84% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
DL
Debian Linux · Debian
9.0 · source: NVD
MU
Mutt · Mutt
before 2.0.2 · source: NVD
NE
Neomutt · Neomutt
before 2020-11-20 · source: NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-28896
CVE.org
https://www.cve.org/CVERecord?id=CVE-2020-28896
Patch
https://github.com/neomutt/neomutt/commit/9c36717a3e2af1f2c1b7242035455ec8112b4b06
Release Notes
https://github.com/neomutt/neomutt/releases/tag/20201120
Patch
https://gitlab.com/muttmua/mutt/-/commit/04b06aaa3e0cc0022b9b01dbca2863756ebbf59a
Patch
https://gitlab.com/muttmua/mutt/-/commit/d92689088dfe80a290ec836e292376e2d9984f8f
Mailing List
https://lists.debian.org/debian-lts-announce/2020/11/msg00048.html
Third Party Advisory
https://security.gentoo.org/glsa/202101-32
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