CVE-2026-47751 Claude Code Action: Malicious MCP Server Configuration in PRs Enables Remote Code Execution and Secret Exfiltration

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 unconditionall...

CVE-2026-47751

CVE-2026-47751 affects Claude Code Action prior to version 1.0.74. Due to the action checking out attacker-controlled PR head branches, reading .mcp.json from the working directory, and unconditionally enabling all MCP servers via enableAllProjectMcpServers, an attacker could trigger arbitrary co...