Claude Code: Plugin Hash Pin Bypass Allows Bypass of Hash Pinning

Why it is Yellow

• CVSS 7.5 high
• Remotely exploitable without logging in
• On your watchlist: npm

Affected packages

References

• https://github.com/advisories/GHSA-pq7j-f95f-qfcv
• https://github.com/anthropics/claude-code/security/advisories/GHSA-pq7j-f95f-qfcv
• https://nvd.nist.gov/vuln/detail/CVE-2026-86063
• https://github.com/anthropics/claude-code/releases/tag/v2.1.179
• https://github.com/advisories/GHSA-pq7j-f95f-qfcv

Original description

Claude Code is an agentic coding tool. Prior to 2.1.179, the Claude Code and Claude Desktop plugin installation flow runs git checkout for a marketplace-pinned commit without verifying that the resulting HEAD equals the pinned 40-character SHA. An attacker who controls a plugin repository on a Git host that permits SHA-shaped branch names can create a branch named after the reviewed commit, causing checkout to select the branch tip and install attacker-controlled plugin code. Exploitation requires a user to install the malicious plugin and pin it to the ostensibly safe hash. This issue is fixed in version 2.1.179.