Bug 2551595 (CVE-2026-86063)

Summary:	CVE-2026-86063 claude-code: Claude Code: arbitrary code execution via unverified commit hash during plugin installation
Product:	[Other] Security Response	Reporter:	OSIDB Bzimport <bzimport>
Component:	vulnerability	Assignee:	Product Security DevOps Team <prodsec-dev>
Status:	NEW ---	QA Contact:
Severity:	high	Docs Contact:
Priority:	high
Version:	unspecified	CC:	sdawley
Target Milestone:	---	Keywords:	Security
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Hardware:	All
OS:	Linux
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Doc Text:	A flaw was found in Claude Code. When installing a plugin pinned to a specific commit hash, the application does not verify that the checked-out version matches the expected Secure Hash Algorithm (SHA) identifier. A remote attacker controlling a repository can create a branch named after the reviewed commit hash, tricking the tool into installing attacker-controlled code instead of the approved version. If a user installs the plugin, this issue can lead to arbitrary code execution.	Story Points:	---
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oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
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Description OSIDB Bzimport 2026-10-13 20:50:43 UTC

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.