CVE-2026-119234: Facebook mvfst · Unthrottled Resource Allocation
Affects Facebook mvfstSource CVE Database V5
Not known to be exploited : upgrade to v2026.11.09.0 soon.
Data as of 11 Nov 2026, 17:31 UTC
Rated High by Threat Radar's AI analysis · CVSS not yet scored by NVD
Thin evidence
One scorer or none- Patch
- Available – fixed in v2026.11.09.0
Exploitation evidence
Disclosed: evidence found.
CVE published 11 Nov 2026
Detectable: no evidence on record.
No public nuclei template indexed
Weaponized: no evidence on record.
No public exploit code indexed in Metasploit or Exploit-DB
Exploited in the wildExploited: no evidence on record.
Not in CISA KEV and no source reports exploitation
Observed by OffSeq MirageSeen by Mirage: no evidence on record.
No attack traffic recorded by OffSeq Mirage sensors
A missing step is not evidence of safety. Sources: cve.org (opens in a new tab), the Metasploit, Exploit-DB and nuclei-templates index as of 11 Nov 2026.
What to do
Upgrade Facebook mvfst to v2026.11.09.0.
Affected software
| Product | Affected | Fixed in |
|---|---|---|
| Facebookmvfst | Affected
| Fixed in
|
AI-suggested
Upgrade mvfst to version v2026.11.09.0 or later, where this vulnerability has been fixed. No additional mitigation is required once the update is applied.
Description
A vulnerability in Facebook's mvfst prior to version 2026.11.09.0 allows a remote unauthenticated QUIC peer to cause excessive memory consumption and CPU usage by sending many small, non-contiguous stream fragments. This happens because mvfst does not properly merge or compact out-of-order STREAM frame data, leading to denial of service.