GitHub CLI: Attestation Verification Bypass via Unescaped Regex Metacharacters in SAN Matching
- Published
- Last modified
- Where the record stands: published, rejected by its publisher, or superseded by another id.What do these mean? →
- published
- Whether CISA lists it in its Known Exploited Vulnerabilities catalog: proof that attackers are using it.What do these mean? →
- Not listed in CISA KEV
- Fix
- Fixed in 2.97.0
- Whether working attack code is public (Exploit-DB, Metasploit, Nuclei or GitHub). Public code makes attacks easier.What do these mean? →
- None on Exploit-DB, Metasploit or GitHub
- Exploitation: none
- Automatable: yes
- Technical impact: partial
Summary
GitHub CLI (gh) is GitHub’s official command line tool. Prior to 2.97.0, gh attestation verify builds the certificate Subject Alternative Name matcher from the --signer-repo and --signer-workflow flag values without escaping regex metacharacters, so a user-supplied repository or workflow name is treated as a regular expression rather than a literal string. Because GitHub permits characters such as `.` in organization, repository, and workflow path names and `.` is a regex wildcard, an attacker can register a lookalike name (for example github/artifact.attestations-workflows) that satisfies a matcher intended for a different trusted signer (github/artifact-attestations-workflows), bypassing the intended Sigstore attestation verification. Exploitation requires the attacker to create a plausible lookalike repository and produce valid attestations from it, which could undermine supply chain verification for CI/CD pipelines or policy gates that pin trust to a specific signing workflow. This issue is fixed in version 2.97.0.
Timeline
- CVE published
- CISA SSVC assessment
Exploitation: none · Automatable: yes · Technical impact: partial
- Record last updated
Affected versions
- cli cli
fixed in 2.97.0
- github.com/cli/cli/v2Go
fixed in 2.97.0
- github.com/cli/cliGo
All versions