{"id":"CVE-2026-40911","state":"PUBLISHED","title":"WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks","description":"WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin's WebSocket server relays attacker-supplied JSON message bodies to every connected client without sanitizing the `msg` or `callback` fields. On the client side, `plugin/YPTSocket/script.js` contains two `eval()` sinks fed directly by those relayed fields (`json.msg.autoEvalCodeOnHTML` at line 568 and `json.callback` at line 95). Because tokens are minted for anonymous visitors and never revalidated beyond decryption, an unauthenticated attacker can broadcast arbitrary JavaScript that executes in the origin of every currently-connected user (including administrators), resulting in universal account takeover, session theft, and privileged action execution. Commit c08694bf6264eb4decceb78c711baee2609b4efd contains a fix.","publishedAt":"2026-04-21T19:55:37.195Z","updatedAt":"2026-04-22T13:22:26.143Z","severity":{"score":10,"label":"Critical","version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","source":"GitHub_M"},"assigner":"GitHub_M","products":["WWBN AVideo"],"affected":[{"vendor":"WWBN","product":"AVideo","versions":[{"version":"<= 29.0","status":"affected"}]}],"references":["https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr","https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd"],"weaknesses":["CWE-94"],"ingestedAt":"2026-10-29T20:11:57.932Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/40xxx/CVE-2026-40911.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-40911","state":"PUBLISHED","datePublished":"2026-04-21T19:55:37.195Z","dateUpdated":"2026-04-22T13:22:26.143Z","assignerShortName":"GitHub_M","assignerOrgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateReserved":"2026-04-15T16:37:22.768Z"},"containers":{"cna":{"title":"WWBN AVideo YPTSocket WebSocket Broadcast Relay Leads to Unauthenticated Cross-User JavaScript Execution via Client-Side eval() Sinks","descriptions":[{"lang":"en","value":"WWBN AVideo is an open source video platform. In versions 29.0 and prior, the YPTSocket plugin's WebSocket server relays attacker-supplied JSON message bodies to every connected client without sanitizing the `msg` or `callback` fields. On the client side, `plugin/YPTSocket/script.js` contains two `eval()` sinks fed directly by those relayed fields (`json.msg.autoEvalCodeOnHTML` at line 568 and `json.callback` at line 95). Because tokens are minted for anonymous visitors and never revalidated beyond decryption, an unauthenticated attacker can broadcast arbitrary JavaScript that executes in the origin of every currently-connected user (including administrators), resulting in universal account takeover, session theft, and privileged action execution. Commit c08694bf6264eb4decceb78c711baee2609b4efd contains a fix."}],"affected":[{"vendor":"WWBN","product":"AVideo","versions":[{"version":"<= 29.0","status":"affected"}]}],"references":[{"url":"https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr","name":"https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr","tags":["x_refsource_CONFIRM"]},{"url":"https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd","name":"https://github.com/WWBN/AVideo/commit/c08694bf6264eb4decceb78c711baee2609b4efd","tags":["x_refsource_MISC"]}],"metrics":[{"cvssV3_1":{"attackComplexity":"LOW","attackVector":"NETWORK","availabilityImpact":"HIGH","baseScore":10,"baseSeverity":"CRITICAL","confidentialityImpact":"HIGH","integrityImpact":"HIGH","privilegesRequired":"NONE","scope":"CHANGED","userInteraction":"NONE","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H","version":"3.1"}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-94","lang":"en","description":"CWE-94: Improper Control of Generation of Code ('Code Injection')","type":"CWE"}]}],"providerMetadata":{"shortName":"GitHub_M","orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","dateUpdated":"2026-04-21T19:55:37.195Z"},"source":{"advisory":"GHSA-gph2-j4c9-vhhr","discovery":"UNKNOWN"}},"adp":[{"title":"CISA ADP Vulnrichment","references":[{"url":"https://github.com/WWBN/AVideo/security/advisories/GHSA-gph2-j4c9-vhhr","tags":["exploit"]}],"metrics":[{"other":{"type":"ssvc","content":{"timestamp":"2026-04-22T13:21:59.998968Z","id":"CVE-2026-40911","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":"2026-04-22T13:22:26.143Z"}}]}}}