CVE-2021-42096
CVE-2021-42096 is a medium-severity vulnerability in Gnu Mailman with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-307.
Key facts
- Severity: Medium (CVSS 3.x base score 4.3)
- CVSS v2: 4.0
- EPSS exploit prediction: 1% (65th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-307
- Affected product: Gnu Mailman
- Published:
- Last modified:
Description
GNU Mailman before 2.1.35 may allow remote Privilege Escalation. A certain csrf_token value is derived from the admin password, and may be useful in conducting a brute-force attack against that password.
Frequently asked questions
- What is CVE-2021-42096?
- GNU Mailman before 2.1.35 may allow remote Privilege Escalation. A certain csrf_token value is derived from the admin password, and may be useful in conducting a brute-force attack against that password.
- How severe is CVE-2021-42096?
- CVE-2021-42096 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
- Is CVE-2021-42096 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (65th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2021-42096?
- CVE-2021-42096 primarily affects Gnu Mailman. In total, 2 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2021-42096?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
- When was CVE-2021-42096 published?
- CVE-2021-42096 was published on 2021-10-21 and last updated on 2026-06-17.
References
- http://www.openwall.com/lists/oss-security/2021/10/21/4
- https://bugs.launchpad.net/mailman/+bug/1947639
- https://mail.python.org/archives/list/mailman-announce%40python.org/thread/IKCO6JU755AP5G5TKMBJL6IEZQTTNPDQ/
- https://www.debian.org/security/2021/dsa-4991
Affected products (2)
- cpe:2.3:a:gnu:mailman:*:*:*:*:*:*:*:*
- cpe:2.3:o:debian:debian_linux:10.0:*:*:*:*:*:*:*
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