CVE-2026-119236
What it is
An mvfst QUIC server retained CRYPTO frame data received at an encryption level (Initial or Handshake) that the TLS handshake had already moved past. Because the transport treated this data as delivered, it did not count against the CRYPTO stream buffer limit. A remote, unauthenticated client could complete a handshake, withhold its acknowledgment of the server's HANDSHAKE_DONE frame so that Handshake keys stay in use, and keep sending Handshake-level CRYPTO data at increasing offsets, causing unbounded memory growth on the server and leading to denial of service. This issue affects mvfst versions prior to v2026.11.09.00.
At a glance
- Fix
- A patch, advisory or fixed version is referenced. Upgrade or apply it.
Timeline
- PublishedDisclosed publicly on CVE.org and NVD
- Last updatedMost recent change to the record
Why it ranks here
- Exploited in the wild: no, CISA does not list it.
- Exploit odds: not scored yet.
- Severity: not scored yet.
- Fix: a patch or advisory is linked.
Details
- Published
- Last modified
- Record status
- Received
Is it in your code?
Hand this to your coding agent. It searches your project for the affected products and checks versions. Nothing leaves your machine.
Read https://cve-list.com/agent/cve/CVE-2026-119236.md and follow it. Check whether this project is affected by CVE-2026-119236. Read only. Don't change anything and don't upload my code. Tell me yes, no or not sure, with the file as proof.
