CVE-2026-91095CWE-416

CVE-2026-91095

Medium · published September 29, 2026

CVSS v3.1
5.3
EPSS
0%
Percentile
15.1
In the wild
Unconfirmed
What it is

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.

The record
Technical detail
CVSS v3.1
5.3 · MEDIUM
Vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
CVSS v4.0
Not supplied
EPSS
0.00247 · 15.1th percentile
Weakness
CWE-416 · Use After Free
Published
2026-09-29T01:17Z
References (2)
https://github.com/facebook/proxygen/commit/479eb5574195764e80e6cedebef669f6baa85083 · [email protected]https://www.facebook.com/security/advisories/cve-2026-91095 · [email protected]
EPSS history
Timeline
  • 30 SEP 03:29Z
    EPSS moved — → 0%
    epss
  • 28 SEP 20:44Z
    In proxygen from v2024.10.28.00 until v2026.09.28.00, the HTTPTransaction::onWebTransportUniStream and HTTPTransaction::onWebTransportBidiStream APIs could…
    cvelistv5