CVE-2026-64655 (GCVE-0-2026-64655)
Vulnerability from cvelistv5
Published
2026-08-06 18:41
Modified
2026-08-08 02:23
CWE
  • CWE-185 - Incorrect Regular Expression
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.
Impacted products
Vendor Product Version
cli cli Version: < 2.97.0
Create a notification for this product.
Show details on NVD website


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