DescriptionThe expansion of '\h' in the prompt string in bash 4.3 allows remote authenticated users to execute arbitrary code via shell metacharacters placed in 'hostname' of a machine.
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, bugtraq, EDB, Metasploit, Red Hat, Ubuntu, Gentoo, SuSE, Mageia, GitHub code/issues, web search, more)
NVD severitymedium (attack range: remote)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
bash (PTS)wheezy4.2+dfsg-0.1+deb7u3vulnerable
wheezy (security)4.2+dfsg-0.1+deb7u4vulnerable
buster, sid, stretch4.4-5fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs

Fixed bin Bash upstream bash-4.4
This doesn't cross any reasonable security boundaries, an attacker with the
ability to modify the hostname in an arbitrary manner is in the position to
exploit various other system components anyway
Fixed by (4.3):

Search for package or bug name: Reporting problems