CVE-2026-42073 (GCVE-0-2026-42073)

Vulnerability from cvelistv5 – Published: 2026-06-02 15:38 – Updated: 2026-06-02 17:40
VLAI
Title
OpenClaude's MCP OAuth Callback: State Check Bypass via error Param Leads to DoS
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-02 17:37 UTC
CWE
  • CWE-352 - Cross-Site Request Forgery (CSRF)
  • CWE-400 - Uncontrolled Resource Consumption
Assigner
GitHub_M CNA
References
Impacted products
Vendor Product Version
Gitlawb openclaude Affected: < 0.5.1
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