CVE-2026-69209
highHttp4s is a Scala interface for HTTP services.
Http4s is a Scala interface for HTTP services. Prior to 0.23.35 and 1.0.0-M47, The shared WebSocket decoder permits unbounded message buffering because defragmentation accumulates fragments without a limit and FrameTranscoder accepts declared lengths up to Int.MaxValue. A remote client that completes a WebSocket handshake against an http4s-blaze-server or http4s-ember-server endpoint can exhaust server memory with oversized frames or fragmented messages. The patched decoder applies a configurable 64 MiB default limit to individual frames and defragmented messages through EmberServerBuilder.withMaxWebSocketMessageSize. This issue is fixed in versions 0.23.35 and 1.0.0-M47.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Affected products
Not reported by the source (unknown — not "none").
Weakness classification (CWE)
Source: NVD / CISA. “NVD-CWE-Other” and “NVD-CWE-noinfo” mean NVD could not assign a specific weakness.
Mitigation & advisories
No vendor advisory or patch reference tagged by NVD. Check the references below.
References
- https://github.com/http4s/http4s/commit/d578c3c9da6193627d40fa785e612cda7fcd77b3 security-advisories@github.com
- https://github.com/http4s/http4s/releases/tag/v0.23.35 security-advisories@github.com
- https://github.com/http4s/http4s/releases/tag/v1.0.0-M47 security-advisories@github.com
- https://github.com/http4s/http4s/security/advisories/GHSA-jrxx-w2m8-5hf5 security-advisories@github.com