CVE-2014-6278: GNU Bash OS Command Injection Vulnerability

High severity, CVSS 8.8. Actively exploited: in CISA KEV since 2025-10-02. EPSS: 99.7% chance of exploitation in the next 30 days.

GNU Bash through 4.3 bash43-026 does not properly parse function definitions in the values of environment variables, which allows remote attackers to execute arbitrary commands via a crafted environment, as demonstrated by vectors involving the ForceCommand feature in OpenSSH sshd, the mod_cgi and mod_cgid modules in the Apache HTTP Server, scripts executed by unspecified DHCP clients, and other situations in which setting the environment occurs across a privilege boundary from Bash execution. NOTE: this vulnerability exists because of an incomplete fix for CVE-2014-6271, CVE-2014-7169, and CVE-2014-6277.

Affected products

• GNU Bash: version 1.14.0 only; version 1.14.1 only; version 1.14.2 only; version 1.14.3 only; version 1.14.4 only; version 1.14.5 only; …

Published 2014-09-30. Last modified 2026-06-17.