#VU58348 Use of Cryptographically Weak Pseudo-Random Number Generator (PRNG) in Mailman - CVE-2021-42096

Vulnerability identifier: #VU58348

Vulnerability risk: Medium

CVSSv4.0: 1.3 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N/E:U/U:Green]

CVE-ID: CVE-2021-42096

CWE-ID: CWE-338

Exploitation vector: Network

Exploit availability: No

Vulnerable software:
Mailman
Web applications / Webmail solutions

Vendor: GNU

Description

The vulnerability allows a remote attacker to brute-force the administrative password.

The vulnerability exists due to a certain csrf_token value is derived from the admin password. A remote attacker can conduct a brute-force attack against that password and gain unauthorized access to the application.

Mitigation
Install updates from vendor's website.

Vulnerable software versions

Mailman: 2.0 - 2.1.34

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External links
https://mail.python.org/archives/list/mailman-announce@python.org/thread/IKCO6JU755AP5G5TKMBJL6IEZQTTNPDQ/
https://bugs.launchpad.net/mailman/+bug/1947639
https://www.openwall.com/lists/oss-security/2021/10/21/4

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Q & A

Can this vulnerability be exploited remotely?

Yes. This vulnerability can be exploited by a remote authenticated user via the Internet.

Is there known malware, which exploits this vulnerability?

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