CVE-2025-43921: mailman vulnerability

GNU Mailman 2.1.39, as bundled in cPanel (and WHM), allows unauthenticated attackers to create lists via the /mailman/create endpoint. NOTE: multiple third parties report that they are unable to reproduce this, regardless of whether cPanel or WHM is used.
CVE-2025-43921CVSS 5.3Runtime

CVE-2025-43921: mailman vulnerability

GNU Mailman 2.1.39, as bundled in cPanel (and WHM), allows unauthenticated attackers to create lists via the /mailman/create endpoint. NOTE: multiple third parties report that they are unable to reproduce this, regardless of whether cPanel or WHM is used.

CVSS
5.3 MEDIUM
EPSS
29.96%
Known exploited
not in KEV
Product
mailman

What is known

GNU Mailman 2.1.39, as bundled in cPanel (and WHM), allows unauthenticated attackers to create lists via the /mailman/create endpoint. NOTE: multiple third parties report that they are unable to reproduce this, regardless of whether cPanel or WHM is used.

Sources

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