CVE-2026-77156 ast-cli: Path traversal in tar extraction on Linux/macOS allows writes outside the install directory
- Exploited in the wild
- Not known
- Fix
- None listed
What is CVE-2026-77156?
CVE-2026-77156 is a medium-severity vulnerability in github.com/checkmarx/ast-cli, published on 22 Oct 2026.
Official description
Incomplete validation of extracted archive entry paths in ast-cli's tar extraction logic on Linux and macOS (used when installing the Vorpal ASCA real-time engine and the SCA Resolver) would allow a malicious tar archive containing absolute or traversal path entries to write files outside the install directory. Windows builds were not affected, as the Windows extractor performs this path validation.
Exploitation required substituting the archive served at "download.checkmarx.com". An attacker able to compromise that server and replace the archive could write arbitrary, executable files to arbitrary filesystem paths via this path traversal.
Extraction now validates that each entry's destination path resolves within the working directory and rejects absolute paths.
Weakness: CWE-22
Which versions are affected by CVE-2026-77156?
How do I fix CVE-2026-77156?
No fix has been published for CVE-2026-77156 yet. Limit exposure of the affected software until one is available.
Is CVE-2026-77156 being exploited?
There is no known exploitation of CVE-2026-77156 in the wild and no public exploit code.
Sources
Also known as GHSA-9gff-3q53-q75x.