{"schemaVersion":3,"id":"CVE-2026-91095","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"In proxygen from v2024.10.28.00 until v2026.09.28.00, the HTTPTransaction::onWebTransportUniStream and HTTPTransaction::onWebTransportBidiStream APIs could return stream handles that the stream handler had already freed. HQSession then installed those handles as transport read callbacks, which could lead to use of freed memory.","dates":{"published":"2026-09-28T20:44:45.928Z","modified":"2026-09-30T19:49:15.429Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":5.3,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":5.3,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":5.3,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00247,"percentile":0.1499,"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":0.00247,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00247,"percentile":0.1499}],"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":0.00247,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00247,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00247,"percentile":0.1499}]},"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-2026-91095","label":"www.facebook.com/security/advisories/cve-2026-91095","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":"2026-09-28T20:44:45.928Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-09-30T19:49:15.429Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":21,"level":"low","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-21T03:38:53.373Z","stale":false,"partial":false}}