{"id":"CVE-2026-86063","aliases":["GHSA-pq7j-f95f-qfcv"],"url":"https://o3.security/vulnerability/CVE-2026-86063","summary":"Claude Code: Plugin Hash Pin Bypass Allows Bypass of Hash Pinning","details":"The plugin install flow in Claude Code and Claude Desktop checked out a marketplace's pinned commit SHA using `git checkout` without verifying that the resulting HEAD matched the pinned SHA. An attacker controlling a plugin's upstream repository could create a branch named identically to the pinned 40-character SHA, causing the checkout to silently resolve to the attacker's branch tip instead of the reviewed commit, resulting in attacker-controlled code being installed bypassing the pinned hash. Exploitation required a user to install a malicious plugin, pin to a safe hash, and for the plugin source to be hosted on a git host that permitted SHA-shaped branch names.\n\nUsers on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version.\n\nThank you to Or Nevo Michrowski of Air Security for reporting this issue.","published":"2026-10-13T19:04:11.695Z","modified":"2026-10-21T03:00:31.775018519Z","cvss":null,"epss":null,"cisaKev":null,"exploitsKnown":null,"affectedPackages":[{"ecosystem":"npm","name":"@anthropic-ai/claude-code","fixedVersion":"2.1.179"}],"fix":null,"references":[{"type":"WEB","url":"https://github.com/anthropics/claude-code/releases/tag/v2.1.179"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/86xxx/CVE-2026-86063.json"},{"type":"ADVISORY","url":"https://github.com/anthropics/claude-code/security/advisories/GHSA-pq7j-f95f-qfcv"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-86063"},{"type":"PACKAGE","url":"https://github.com/anthropics/claude-code"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-10-21T03:00:31.775018519Z"}}