CVE-2026-86063
Claude Code: Plugin Hash Pin Bypass Allows Bypass of Hash Pinning
Published Oct 13, 2026 · corrected/updated Oct 15, 2026 · anthropics claude-code · evidence confidence high
The plugin install flow in Claude Code and Claude Desktop checked out a marketplace's pinned commit SHA using 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. Users on standard Claude Code auto-update have received this fix already. Users performing manual updates are advised to update to the latest version. Thank you to Or Nevo Michrowski of Air Security for reporting this issue.
Grounded briefings
Catalog interpretations for three audiences. Each brief cites ingested metadata and the original advisories below. They are not independent research and they do not invent exploit steps.
Executive
CVE-2026-86063 is a high public vulnerability record for anthropics claude-code. It is not currently listed in the CISA Known Exploited catalog. Check the linked vendor or CERT advisories for patch status. This summary is a catalog interpretation of the ingested metadata and cites the original advisories below.
System administrator
Identify whether anthropics claude-code is in your estate, then compare installed versions with the affected ranges. Affected packages or ranges on record: @anthropic-ai; @anthropic-ai/claude-code (0 → 2.1.179); @anthropic-ai/claude-code (< 2.1.179); anthropics claude-code. Check the linked vendor or CERT advisories for patch status. Prefer the vendor or distribution advisory linked in Sources before changing production systems. This is a catalog interpretation, not a runbook.
Security analyst
Signals on file: CVSS 7.5. It is not currently listed in the CISA Known Exploited catalog. Weakness classes: CWE-494, CWE-829. Sources contributing to this record: cve_org, github, gitlab, osv. Public exploit references, when present, are outbound links only and are not proof of active exploitation. This is a catalog interpretation of stored metadata.
Exploitation and remediation
Exploitation evidence
Not listed as known exploited in CISA KEV. Not in the CISA KEV catalog.
Patch and remediation
No required-action text is stored yet. Use the vendor or CERT links in Sources for patch availability.
Safe detection guidance
Compare installed versions with the affected ranges below and verify the advisory from the original publisher. This site stores metadata and outbound links only; it does not ship exploit code or proof-of-concept payloads.
Code
The project this record applies to. Exploit listings stay in References.
Timeline
Detection, updates, and resolution for this record.
Oct 15, 2026 · GitHub Advisory Database
Detected
The plugin install flow in Claude Code and Claude Desktop checked out a marketplace's pinned commit SHA using 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 com
Oct 15, 2026 · GitHub Advisory Database
Fix available
@anthropic-ai/claude-code fixed in 2.1.179
Oct 15, 2026 · GitHub Advisory Database
Fix available
@anthropic-ai/claude-code fixed in 2.1.179
Oct 15, 2026 · GitHub Advisory Database
Updated
The plugin install flow in Claude Code and Claude Desktop checked out a marketplace's pinned commit SHA using 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 com
Affected
- npm @anthropic-aiversion unspecified
- npm @anthropic-ai/claude-code0 → 2.1.179
- npm @anthropic-ai/claude-code< 2.1.179
- vendor anthropics claude-codeversion unspecified
Sources
- CVE.orgVulnerability recordCVE-2026-86063
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 r
cve.org - GitHub Advisory DatabasePackage advisoryGHSA-pq7j-f95f-qfcv
GitHub Advisory Database record mirrored by OSV.
github.com - GitLab Advisory DatabasePackage advisoryCVE-2026-86063
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
advisories.gitlab.com - OSV.devPackage advisoryGHSA-pq7j-f95f-qfcv
Claude Code: Plugin Hash Pin Bypass Allows Bypass of Hash Pinning
osv.dev