CVE-2026-47751

Claude Code Action is a general-purpose GitHub action that runs Claude Code on GitHub pull requests and issues. Prior to 1.0.74, because the action checked out attacker-controlled pull request head branches, read .mcp.json from the working directory via default setting sources, and unconditionally enabled all project MCP servers via enableAllProjectMcpServers, an attacker who opened a pull request containing a malicious .mcp.json file could achieve arbitrary code execution on the GitHub Actions runner and exfiltrate secrets available to the workflow (such as API keys and tokens) when a privileged user or an automatic trigger invoked the Claude action on the pull request. This issue is fixed in version 1.0.74, which restores .claude/ and .mcp.json from the pull request base branch before the CLI runs.

CVSS

No CVSS.

References

Link	Resource
https://github.com/anthropics/claude-code-action/commit/9ddce40de8c1ab71fb6303a125fdad0968dc1312
https://github.com/anthropics/claude-code-action/pull/1066
https://github.com/anthropics/claude-code-action/releases/tag/v1.0.74
https://github.com/anthropics/claude-code-action/security/advisories/GHSA-8q5r-mmjf-575q

Configurations

No configuration.

History

16 Jul 2026, 17:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-07-16 17:16

Updated : 2026-07-18 03:16

NVD link : CVE-2026-47751

Mitre link : CVE-2026-47751

CVE.ORG link : CVE-2026-47751

JSON object : View

Products Affected

No product.

CWE

CWE-78

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CWE-200

Exposure of Sensitive Information to an Unauthorized Actor

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