CVE-2026-119234 facebook mvfst
facebook mvfst: no CVSS score yet. EPSS 0.2% estimated probability of exploitation activity in the next 30 days.
mvfst did not adequately merge or compact out-of-order STREAM frame data, and a small received fragment could keep a much larger receive buffer alive. QUIC flow control limits the number of buffered stream bytes, but not this per-fragment memory and bookkeeping. A remote, unauthenticated QUIC peer could send many small, non-contiguous stream fragments to make an endpoint consume memory far in excess of its advertised receive window and spend increasing CPU time reassembling stream data, leading to denial of service. This issue affects mvfst versions prior to v2026.11.09.0.
- EPSS
- 0.2% estimated probability of exploitation activity in the next 30 days; 7th percentile. Scored 2026-11-13. A forecast for this CVE across the internet, not for your own systems.
- Published
- Modified
- Assigned by
- Meta (CNA)
- NVD analysis
- Awaiting analysis
- Record from
- the NVD, synced
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Affected
Versions
From the CNA's record in the CVE List.
| Product | Affected |
|---|---|
| Facebook mvfst | from v0.0.0.0 before v2026.11.09.0 |