{"id":"CVE-2026-42889","state":"PUBLISHED","title":"Relay Server WebSocket authentication bypass when token is omitted","description":"Relay adds real-time collaboration to Obsidian. Relay Server versions 0.9.0 through 0.9.6 contain an authentication bypass in the multi-document WebSocket endpoints. When authentication is configured, WebSocket connections without a token query parameter were incorrectly treated as having full server permissions. An unauthenticated network attacker who knows or guesses a document ID could connect to the document sync WebSocket and read or modify document contents without a valid document token. This vulnerability is fixed in 0.9.7.","publishedAt":"2026-05-12T19:30:05.552Z","updatedAt":"2026-05-13T12:32:58.746Z","severity":{"score":9.1,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","source":"GitHub_M"},"assigner":"GitHub_M","products":["No-Instructions relay-server"],"affected":[{"vendor":"No-Instructions","product":"relay-server","versions":[{"version":">= 0.9.0, < 0.9.7","status":"affected"}]}],"references":["https://github.com/No-Instructions/relay-server/security/advisories/GHSA-9vp9-8q9j-8mqm"],"weaknesses":["CWE-863","CWE-639"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/42xxx/CVE-2026-42889.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-42889","state":"PUBLISHED","datePublished":"2026-05-12T19:30:05.552Z","dateUpdated":"2026-05-13T12:32:58.746Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-30T18:49:06.712Z"},"containers":{"cna":{"title":"Relay Server WebSocket authentication bypass when token is omitted","descriptions":[{"lang":"en","value":"Relay adds real-time collaboration to Obsidian. Relay Server versions 0.9.0 through 0.9.6 contain an authentication bypass in the multi-document WebSocket endpoints. When authentication is configured, WebSocket connections without a token query parameter were incorrectly treated as having full server permissions. An unauthenticated network attacker who knows or guesses a document ID could connect to the document sync WebSocket and read or modify document contents without a valid document token. This vulnerability is fixed in 0.9.7."}],"affected":[{"vendor":"No-Instructions","product":"relay-server","versions":[{"version":">= 0.9.0, < 0.9.7","status":"affected"}]}],"references":[{"url":"https://github.com/No-Instructions/relay-server/security/advisories/GHSA-9vp9-8q9j-8mqm","name":"https://github.com/No-Instructions/relay-server/security/advisories/GHSA-9vp9-8q9j-8mqm","tags":["x_refsource_CONFIRM"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"NONE","baseScore":9.1,"baseSeverity":"CRITICAL","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"UNCHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-863","lang":"en","description":"CWE-863: Incorrect Authorization","type":"CWE"}]},{"descriptions":[{"cweId":"CWE-639","lang":"en","description":"CWE-639: Authorization Bypass Through User-Controlled Key","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-05-12T19:30:05.552Z"},"source":{"advisory":"GHSA-9vp9-8q9j-8mqm","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/No-Instructions/relay-server/security/advisories/GHSA-9vp9-8q9j-8mqm","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-05-13T12:32:29.545243Z","id":"CVE-2026-42889","options":[{"Exploitation":"poc"},{"Automatable":"yes"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-05-13T12:32:58.746Z"}}]}}}