Shellshock Bash Bug

Shellshock Bash Bug

Everyone’s probably heard of the Shellshock Bash bug by now, which was announced with CVE-2014-6271 on September 24, 2014.  According to the announcement:

GNU Bash through 4.3 processes trailing strings after function definitions in the values of environment variables, which allows remote attackers to execute arbitrary code 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, aka “ShellShock.”

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