{"id":"CVE-2026-64655","title":"GitHub CLI (gh) is GitHub’s official command line tool","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 meta…","severity":"low","cwe":["CWE-185"],"published":"2026-08-06","updated":"2026-09-10","sourceUpdated":"2026-09-10T20:36:14.340","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-64655","references":[{"url":"https://github.com/cli/cli/commit/55dbb4dc6b7edb10b48e3d7fc5bccd32318d1b55","label":"security-advisories@github.com"},{"url":"https://github.com/cli/cli/releases/tag/v2.97.0","label":"security-advisories@github.com"},{"url":"https://github.com/cli/cli/security/advisories/GHSA-mm27-mwq9-fr5g","label":"security-advisories@github.com"},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-64655"},{"url":"https://github.com/advisories/GHSA-mm27-mwq9-fr5g"},{"url":"https://github.com/cli/cli"}],"tags":["nvd","ghsa","go","osv"],"epss":0.00343,"epssPercentile":0.27697,"ingestedAt":"2026-08-09T00:31:25.091Z","aliases":["GHSA-mm27-mwq9-fr5g","GO-2026-6767"],"ecosystem":"go","vendor":"cli","product":"github.com/cli/cli/v2","affected":["github.com/cli/cli/v2 < 2.97.0"],"patched":["github.com/cli/cli/v2 2.97.0"],"slug":"CVE-2026-64655","body":"## Overview\n\nGitHub 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.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-64655)\n\nAffected packages:\n\n- `github.com/cli/cli/v2 < 2.97.0`\n\nPatched in:\n\n- `github.com/cli/cli/v2 2.97.0`\n\nSource: https://github.com/advisories/GHSA-mm27-mwq9-fr5g","depth":"sunlit","depthScore":14,"depthScoreParts":{"impact":13.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":222645,"id":"CVE-2026-64655","ts":1792088728042,"field":"severity","old":"none","new":"low"}]}