{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-84894","assignerOrgId":"4fc57720-52fe-4431-a0fb-3d2c8747b827","state":"PUBLISHED","assignerShortName":"Meta","dateReserved":"2026-09-02T14:52:36.354Z","datePublished":"2026-09-28T18:40:55.707Z","dateUpdated":"2026-09-30T15:05:50.817Z"},"containers":{"cna":{"affected":[{"defaultStatus":"unaffected","product":"moxygen","vendor":"Meta Platforms, Inc","versions":[{"lessThan":"004123dd24c30dad6b649163575145f240dabc94","status":"affected","version":"b24f8e65cb83ebe5f3880cc4e3a4c8f64e1882f9","versionType":"git"}]}],"dateAssigned":"2026-09-02T00:00:00.000Z","descriptions":[{"lang":"en","value":"In moxygen before commit 004123dd24c3, MoQSession::dataStreamReadLoop keeps using a stream read handle after reading a FIN, which invalidates the handle under proxygen's WebTransport API. A remote peer can trigger the stale use by opening a data stream that names an unknown track alias and carries the FIN in the same write."}],"problemTypes":[{"descriptions":[{"description":"Use After Free (CWE-416)","lang":"en"}]}],"providerMetadata":{"orgId":"4fc57720-52fe-4431-a0fb-3d2c8747b827","shortName":"Meta","dateUpdated":"2026-09-28T18:40:55.707Z"},"references":[{"tags":["x_refsource_CONFIRM"],"url":"https://www.facebook.com/security/advisories/cve-2026-84894"},{"tags":["x_refsource_MISC"],"url":"https://github.com/facebookexperimental/moxygen/commit/004123dd24c30dad6b649163575145f240dabc94"}]},"adp":[{"problemTypes":[{"descriptions":[{"type":"CWE","cweId":"CWE-416","lang":"en","description":"CWE-416 Use After Free"}]}],"metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":7.5,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","integrityImpact":"NONE","userInteraction":"NONE","attackComplexity":"LOW","availabilityImpact":"NONE","privilegesRequired":"NONE","confidentialityImpact":"HIGH"}},{"other":{"type":"ssvc","content":{"timestamp":"2026-09-30T15:05:21.880556Z","id":"CVE-2026-84894","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"title":"CISA ADP Vulnrichment","providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-30T15:05:50.817Z"}}]}}