{"id":"CVE-2026-42073","state":"PUBLISHED","title":"OpenClaude's MCP OAuth Callback: State Check Bypass via error Param Leads to DoS","description":"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.","publishedAt":"2026-06-02T15:38:53.435Z","updatedAt":"2026-06-02T17:40:55.678Z","severity":{"score":6.5,"label":"Medium","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["Gitlawb openclaude"],"affected":[{"vendor":"Gitlawb","product":"openclaude","versions":[{"version":"< 0.5.1","status":"affected"}]}],"references":["https://github.com/Gitlawb/openclaude/security/advisories/GHSA-c73c-x77g-854r","https://github.com/Gitlawb/openclaude/commit/739b8d1f40fde0e401a5cbd2b9a55d88bd5124ad","https://github.com/Gitlawb/openclaude/releases/tag/v0.5.1"],"weaknesses":["CWE-352","CWE-400"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42073.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42073","state":"PUBLISHED","datePublished":"2026-06-02T15:38:53.435Z","dateUpdated":"2026-06-02T17:40:55.678Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-23T19:17:30.565Z"},"containers":{"cna":{"title":"OpenClaude's MCP OAuth Callback: State Check Bypass via error Param Leads to DoS","descriptions":[{"lang":"en","value":"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":[{"vendor":"Gitlawb","product":"openclaude","versions":[{"version":"< 0.5.1","status":"affected"}]}],"references":[{"url":"https://github.com/Gitlawb/openclaude/security/advisories/GHSA-c73c-x77g-854r","name":"https://github.com/Gitlawb/openclaude/security/advisories/GHSA-c73c-x77g-854r","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/Gitlawb/openclaude/commit/739b8d1f40fde0e401a5cbd2b9a55d88bd5124ad","name":"https://github.com/Gitlawb/openclaude/commit/739b8d1f40fde0e401a5cbd2b9a55d88bd5124ad","tags":["x_refsource_MISC"]},{"url":"https://github.com/Gitlawb/openclaude/releases/tag/v0.5.1","name":"https://github.com/Gitlawb/openclaude/releases/tag/v0.5.1","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":6.5,"baseSeverity":"MEDIUM","confidentialityImpact":"NONE","integrityImpact":"NONE","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"REQUIRED","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-352","lang":"en","description":"CWE-352: Cross-Site Request Forgery (CSRF)","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-400","lang":"en","description":"CWE-400: Uncontrolled Resource Consumption","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-06-02T15:38:53.435Z"},"source":{"advisory":"GHSA-c73c-x77g-854r","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/Gitlawb/openclaude/security/advisories/GHSA-c73c-x77g-854r","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-06-02T17:37:51.060222Z","id":"CVE-2026-42073","options":[{"Exploitation":"poc"},{"Automatable":"no"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-06-02T17:40:55.678Z"}}]}}}