{"schemaVersion":3,"id":"CVE-2026-91096","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"In proxygen from v2024.10.28.00 until v2026.09.28.00, WebTransportImpl::terminateSessionStreams (WebTransportImpl::destroy in releases before v2025.08.18.00) failed to unregister read callbacks for streams that were no longer open before destroying them. The transport could then invoke a read callback that had been freed.","dates":{"published":"2026-09-28T20:44:57.363Z","modified":"2026-09-30T19:47:55.479Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.5,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00255,"percentile":0.16013,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-09-29T00:00:00.000Z","score":0.00145,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00145,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00255,"percentile":0.16013}],"last30":[{"date":"2026-09-29T00:00:00.000Z","score":0.00145,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00145,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00255,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00255,"percentile":0.16013}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-416","name":"Use After Free","description":"The product reuses or references memory after it has been freed. At some point afterward, the memory may be allocated again and saved in another pointer, while the original pointer references a location somewhere within the new allocation. Any operations using the original pointer are no longer valid because the memory \"belongs\" to the code that operates on the new pointer.","type":"weakness","status":"Stable","abstraction":"Variant","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/416.html"}],"affected":[{"vendor":"facebook","product":"proxygen","name":"proxygen","label":"proxygen","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ v2024.10.28.00, < v2026.09.28.00","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ v2024.10.28.00, < v2026.09.28.00","eol":null,"hubHref":"/vendor/facebook/proxygen"}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://www.facebook.com/security/advisories/cve-2026-91096","label":"www.facebook.com/security/advisories/cve-2026-91096","hostname":"www.facebook.com","tags":["X Refsource CONFIRM"]},{"url":"https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083","label":"github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083","hostname":"github.com","tags":["X Refsource MISC"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-09-28T20:44:57.363Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-09-30T19:47:55.479Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":30,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-21T03:17:31.373Z","stale":false,"partial":false}}