CVE-2026-4424

Name	CVE-2026-4424
Description	A flaw was found in libarchive. This heap out-of-bounds read vulnerability exists in the RAR archive processing logic due to improper validation of the LZSS sliding window size after transitions between compression methods. A remote attacker can exploit this by providing a specially crafted RAR archive, leading to the disclosure of sensitive heap memory information without requiring authentication or user interaction.
Source	CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source Package	Release	Version	Status
libarchive (PTS)	bullseye	3.4.3-2+deb11u1	vulnerable
	bullseye (security)	3.4.3-2+deb11u3	vulnerable
	bookworm	3.6.2-1+deb12u3	vulnerable
	bookworm (security)	3.6.2-1+deb12u2	vulnerable
	trixie	3.7.4-4	vulnerable
	forky, sid	3.8.5-1	vulnerable

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

Package	Type	Release	Fixed Version	Urgency	Origin	Debian Bugs
libarchive	source	(unstable)	(unfixed)

https://github.com/libarchive/libarchive/pull/2898