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 bugzilla/CVE, Mageia, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
bash (PTS)buster5.0-4fixed
bookworm, sid5.2.15-2fixed

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):

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