CVE-2026-15343 Path traversal in Enterprise Server
Attacker with container access can write arbitrary files, including workflows, leading to code execution and secret exposure in GitHub Enterprise Server.
- 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-2026-15343?
CVE-2026-15343 is a high-severity path traversal vulnerability in GitHub Enterprise Server, published on 17 Jul 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
A path traversal vulnerability was identified in GitHub Enterprise Server that allowed an attacker who had code execution inside the Dependabot updater container to write files to arbitrary repository paths, including GitHub Actions workflow files under .github/workflows/ as the path validation did not check the effective path which the attacker could control through the dependency file's directory and symlink target. If the repository used a pull_request_target workflow or had auto-merge enabled, an injected workflow could execute with access to the repository's GitHub Actions secrets. This vulnerability affected all versions of GitHub Enterprise Server prior to 3.22 and was fixed in versions 3.21.3, 3.20.5, 3.19.9, 3.18.12, 3.17.18.
Weakness: CWE-22
Which versions are affected by CVE-2026-15343?
How do I fix CVE-2026-15343?
No fix has been published for CVE-2026-15343 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-2026-15343 being exploited?
There is no known exploitation of CVE-2026-15343 in the wild and no public exploit code.
Sources
Also known as GHSA-h327-qh69-cgch.