CVE-2021-42097
Status: ModifiedHigh (8)—
GNU Mailman before 2.1.35 may allow remote Privilege Escalation. A csrf_token value is not specific to a single user account. An attacker can obtain a value within the context of an unprivileged user account, and then use that value in a CSRF attack against an admin (e.g., for account takeover).
CVSS
- Version: 3.1
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:H
- Base score: 8
Exploitation probability (EPSS)
- Probability of exploitation in the next 30 days: 1.33%
- Percentile among all scored CVEs: 70
- Score date: 10/7/2026
EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).
Affected technologies (2)
CWEs
- CWE-352
References
- http://www.openwall.com/lists/oss-security/2021/10/21/4
- https://bugs.launchpad.net/mailman/+bug/1947640
- https://mail.python.org/archives/list/mailman-announce%40python.org/thread/IKCO6JU755AP5G5TKMBJL6IEZQTTNPDQ/
- https://www.debian.org/security/2021/dsa-4991
- http://www.openwall.com/lists/oss-security/2021/10/21/4
- https://bugs.launchpad.net/mailman/+bug/1947640
- https://mail.python.org/archives/list/mailman-announce%40python.org/thread/IKCO6JU755AP5G5TKMBJL6IEZQTTNPDQ/
- https://www.debian.org/security/2021/dsa-4991
Raw JSON (NVD)
Show
{
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"authentication": "SINGLE",
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"published": "2021-10-21T01:15:06.940",
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"value": "GNU Mailman before 2.1.35 may allow remote Privilege Escalation. A csrf_token value is not specific to a single user account. An attacker can obtain a value within the context of an unprivileged user account, and then use that value in a CSRF attack against an admin (e.g., for account takeover)."
},
{
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}
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"lastModified": "2026-06-17T04:09:18.743",
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