CVE-2026-89039 Arbitrary file read via the convert_playwright_script prompt in mcp-k6
Attackers can read arbitrary files, including sensitive credentials, by exploiting path traversal in the convert_playwright_script prompt of mcp-k6.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- None listed
What is CVE-2026-89039?
CVE-2026-89039 is a medium-severity path traversal vulnerability in Grafana mcp-k6, published on 5 Oct 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A caller who can invoke the convert_playwright_script prompt in mcp-k6 can pass a bare file path as the playwright_script argument and receive the contents of any file readable by the user running the server, including SSH keys and cloud credentials in that user's home directory (path traversal). The working-directory restriction applied to '@'-prefixed paths can also be bypassed with a symbolic link inside the working directory that points outside it.
Which versions are affected by CVE-2026-89039?
How do I fix CVE-2026-89039?
No fix has been published for CVE-2026-89039 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-2026-89039 being exploited?
There is no known exploitation of CVE-2026-89039 in the wild and no public exploit code.
Sources
Also known as GHSA-ffg3-vfrj-4mjj.