CVE-2012-3523: ISC Inn

Medium severity, CVSS 6.8. EPSS: 3.2% chance of exploitation in the next 30 days.

The STARTTLS implementation in nnrpd in INN before 2.5.3 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted sessions by sending a cleartext command that is processed after TLS is in place, related to a "plaintext command injection" attack, a similar issue to CVE-2011-0411.

Affected products

• ISC Inn: up to and including 2.5.2; version 1.4 only; version 1.4sec only; version 1.4sec2 only; version 1.4unoff3 only; version 1.4unoff4 only; …

Published 2012-11-11. Last modified 2026-06-16.