CVE-2026-86538 knowns before 0.30.0 Path Traversal via templateFile parameter
Unauthenticated attackers can read arbitrary files via path traversal in the template preview endpoint, exposing sensitive data.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-86538?
CVE-2026-86538 is a high-severity path traversal vulnerability in knowns-dev knowns, published on 7 Sep 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
knowns versions before 0.30.0 contain a path traversal vulnerability in the POST /api/templates/preview endpoint that allows unauthenticated attackers to read arbitrary files. Attackers can supply directory traversal sequences in the templateFile parameter to bypass path restrictions and read sensitive files like credentials and configuration through the JSON response.
Weakness: CWE-22
Which versions are affected by CVE-2026-86538?
How do I fix CVE-2026-86538?
No fix has been published for CVE-2026-86538 yet. Limit exposure of the affected software until one is available.
Upgrade, and resolve every user-supplied path against an allowed base folder before opening it. More about Path traversal.
Is CVE-2026-86538 being exploited?
There is no known exploitation of CVE-2026-86538 in the wild and no public exploit code.
Sources
Also known as GHSA-fpxv-c555-rhm3, GHSA-g3m9-72x4-rrgv.