CVE-2026-42073: Gitlawb Openclaude

Medium severity, CVSS 6.5. EPSS: 0.3% chance of exploitation in the next 30 days.

OpenClaude is an open-source coding-agent command line interface for cloud and local model providers. Prior to version 0.5.1, the OpenClaude MCP authentication flow starts a temporary local HTTP server to handle OAuth callbacks. To prevent CSRF attacks, the server validates a state parameter against an internally stored value. However, due to a logic flaw in the order of conditionals, an attacker can completely bypass this check and force the server to shut down — without knowing the state value at all. This issue has been patched in version 0.5.1.

Affected products

• Gitlawb Openclaude: before 0.5.1 (fixed in 0.5.1)

Published 2026-06-02. Last modified 2026-07-22.