CVE-2011-1926

Severity: medium (CVSS 5.1 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 4.0% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2011-05-23 · updated 2026-06-16
Weakness: CWE-264

Description

The STARTTLS implementation in Cyrus IMAP Server before 2.4.7 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

Cmu Cyrus Imap Server: through 2.4.6; 2.0.17, 2.1.16, 2.1.17, 2.1.18, 2.2.8, 2.2.9 (+28)

References

http://bugzilla.cyrusimap.org/show_bug.cgi?id=3423
http://bugzilla.cyrusimap.org/show_bug.cgi?id=3424
http://git.cyrusimap.org/cyrus-imapd/patch/?id=523a91a5e86c8b9a27a138f04a3e3f2d8786f162
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/061374.html
http://lists.fedoraproject.org/pipermail/package-announce/2011-June/061415.html
http://openwall.com/lists/oss-security/2011/05/17/15
http://openwall.com/lists/oss-security/2011/05/17/2
http://secunia.com/advisories/44670
http://secunia.com/advisories/44876
http://secunia.com/advisories/44913
http://secunia.com/advisories/44928
http://www.cyrusimap.org/docs/cyrus-imapd/2.4.7/changes.php

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