#VU48662 Cleartext transmission of sensitive information in Mutt - CVE-2020-28896

Vulnerability identifier: #VU48662

Vulnerability risk: Medium

CVSSv4.0: 4.9 [CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2020-28896

CWE-ID: CWE-319

Exploitation vector: Local network

Exploit availability: No

Vulnerable software:
Mutt
Client/Desktop applications / Office applications

Vendor: Mutt.org

Description

The vulnerability allows a remote attacker to gain access to sensitive information.

The vulnerability exists due to software does not ensure that $ssl_force_tls is processed if an IMAP server's initial server response is invalid. As a result, the connection is not properly closed, and the application continues authentication attempts. A remote attacker with ability to intercept traffic can perform a MitM attack and gain access to victim's credentials.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mutt: 2.0 - 2.0.1

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External links
https://github.com/neomutt/neomutt/commit/9c36717a3e2af1f2c1b7242035455ec8112b4b06
https://github.com/neomutt/neomutt/releases/tag/20201120
https://gitlab.com/muttmua/mutt/-/commit/04b06aaa3e0cc0022b9b01dbca2863756ebbf59a
https://gitlab.com/muttmua/mutt/-/commit/d92689088dfe80a290ec836e292376e2d9984f8f

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote non-authenticated attacker via the local network (LAN).

Is there known malware, which exploits this vulnerability?

No. We are not aware of malware exploiting this vulnerability.