All vulnerabilities

Servers and applications

CVE-2014-3556

The STARTTLS implementation in mail/ngx_mail_smtp_handler.c in the SMTP proxy in nginx 1.5.x and 1.6.x before 1.6.1 and 1.7.x before 1.7.4 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…

Severity
Medium 6.8
Published
29 Dec 2014
Last changed
17 Jun 2026
Added to UpHeron
21 Oct 2026
Fixed in
1.6.1, 1.7.4
Sources
NVD

Affected software

SoftwareAffected versions
nginxServers and applications · cpe:a:f5:nginx
  • From 1.5.6 before 1.6.1
  • From 1.7.0 before 1.7.4

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2014-3556
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2014-3556