CVE-2026-119233
CVE-2026-119233
proxygen's HTTP/3 codec buffered an incomplete non-DATA frame, such as a control-stream frame, a frame of an unknown or reserved type, or a HEADERS frame, until its entire declared length had arrived, without limiting that length, and re-scanned all buffered data each time more bytes arrived. A remote, unauthenticated HTTP/3 peer could declare a very large frame and deliver it slowly, causing unbounded memory growth and CPU usage that grows quadratically with the number of fragments, leading to denial of service. This issue affects proxygen versions prior to v2026.11.09.00.
Fixes and workarounds
No remediation reported in collected sources.
Missing remediation information is not evidence that no patch exists.
Affected products and versions
| Product | Versions | Authority |
|---|---|---|
| proxygen |
≥ v0.0.0.0; < v2026.11.09.00 (affected, semver)
Other versions: unaffected |
CNA: Meta |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
No CVSS assessment reported. An unscored record is not a low-severity determination.
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://www.facebook.com/security/advisories/cve-2026-119233CNA: Meta · x_refsource_CONFIRM
- https://github.com/meta/proxygen/commit/daf245bba7fe1304b9491403fe56f91153299781CNA: Meta · x_refsource_MISC
- https://github.com/meta/proxygen/commit/daf245bba7fe1304b9491403fe56f91153299781[email protected]
- https://www.facebook.com/security/advisories/cve-2026-119233[email protected]
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