#VU50017 Resource exhaustion in Mutt - CVE-2021-3181

Vulnerability identifier: #VU50017

Vulnerability risk: Medium

CVSSv4.0: 6.6 [CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-3181

CWE-ID: CWE-400

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mutt
Client/Desktop applications / Office applications

Vendor: Mutt.org

Description

The vulnerability allows a remote attacker to perform a denial of service (DoS) attack.

The vulnerability exists due to improper input validation when handling email messages with sequences of semicolon characters in RFC822 address fields. A remote attacker can send a specially crafted email message, force the application to consume a huge amount of memory and perform a denial of service (DoS) attack.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mutt: 2.0.1 - 2.0.4

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External links
https://www.openwall.com/lists/oss-security/2021/01/19/10
https://gitlab.com/muttmua/mutt/-/commit/4a2becbdb4422aaffe3ce314991b9d670b7adf17
https://gitlab.com/muttmua/mutt/-/commit/939b02b33ae29bc0d642570c1dcfd4b339037d19
https://gitlab.com/muttmua/mutt/-/commit/d4305208955c5cdd9fe96dfa61e7c1e14e176a14
https://gitlab.com/muttmua/mutt/-/issues/323

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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 Internet.

Is there known malware, which exploits this vulnerability?

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