CVE-2026-45390 Path traversal in n/a
Attackers can write arbitrary files outside the extraction directory via crafted tar archives in the OCaml-tar library.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-45390?
CVE-2026-45390 is a critical path traversal vulnerability in n/a, published on 15 Jun 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
In OCaml-tar before 3.4.0, a crafted archive with ../ path segments in its name allows escaping the current working directory. This is not desired behavior, and tar(1) rejects such extractions, but ocaml-tar decompresses it anyway. The impact is that it allows arbitrary file writes outside of the desired extraction directory (to an attacker that can reach a tar decompression endpoint).
Weakness: CWE-22
Which versions are affected by CVE-2026-45390?
How do I fix CVE-2026-45390?
Upgrade to a fixed version.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-45390 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-45390 exists.
Sources
Also known as GHSA-x4gv-m4gg-cwm5, OSEC-2026-08.