What’s Vulnerable › Vulnerabilities

CVE-2011-1431

• Severity: medium (CVSS 6.8 v2.0)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 4.6% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2011-03-16 · updated 2026-06-16

Description

The STARTTLS implementation in qmail-smtpd.c in qmail-smtpd in the netqmail-1.06-tls patch for netqmail 1.06 does not properly restrict I/O buffering, which allows man-in-the-middle attackers to insert commands into encrypted SMTP 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

• Frederik Vermeulen Netqmail: 1.06

References

• http://inoa.net/qmail-tls/vu555316.patch
• http://securityreason.com/securityalert/8144
• http://www.kb.cert.org/vuls/id/555316
• http://www.kb.cert.org/vuls/id/MAPG-8D9M5Q
• http://www.postfix.org/CVE-2011-0411.html
• http://www.securityfocus.com/archive/1/516901
• http://www.securityfocus.com/bid/46767
• http://www.vupen.com/english/advisories/2011/0612
• https://exchange.xforce.ibmcloud.com/vulnerabilities/65932
• http://inoa.net/qmail-tls/vu555316.patch
• http://securityreason.com/securityalert/8144
• http://www.kb.cert.org/vuls/id/555316

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