CVE-2026-39246
decompress before 4.2.2 allows arbitrary symlink creation during archive extraction. When processing symlink entries (type === 'symlink'), the x.linkname field from the archive is passed directly to fs.symlink() without validation (index.js line 121). The preventWritingThroughSymlink check on line 98 only applies to file entries, not symlink creation. An attacker can craft an archive with symlink entries pointing to sensitive files outside the extraction directory (e.g., /etc/passwd), enabling information disclosure when the application reads the extracted contents.
A public proof-of-concept or exploit code is available, raising the risk of active exploitation. No distribution fix is listed yet; apply vendor mitigations and monitor.
Recommended action: Track your distribution's security tracker and apply the fix as soon as it ships.
Severity metrics
CVSS 3.1 : 7.5 HIGH
Vector: AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Affected & fixed versions by distribution
Versions are the native distribution strings (backport-aware): RHEL/Debian/SUSE backport fixes, so compare with the distro version comparator (dpkg / rpm / vercmp), not the upstream version.
No affected package in the tracked watchlist yet (Debian, Ubuntu, Arch, SUSE, Red Hat...). Triage may still be pending.