CVE-2026-91096

HIGH CVSS 3.1: 7.5 EPSS 0.26%
Updated Sep 30, 2026
Facebook
Parameter Value
CVSS 7.5 (HIGH)
Type CWE-416 (Use After Free)
Vendor Facebook
Public PoC No

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.

Attack Parameters

Attack Vector
Network
Can be exploited remotely
Attack Complexity
Low
Easy to exploit
Privileges Required
None
No privileges needed
User Interaction
None
No user interaction needed

Impact Assessment

Confidentiality
High
Complete data leak
Integrity
None
No data modification
Availability
None
No disruption

CVSS Vector v3.1

Weakness Type (CWE)

Vulnerable Products

facebook:proxygen