Intel

AIKIDO-2026-829005

http4s-core_3 is vulnerable to Denial of Service (DoS)

Denial of Service (DoS)GHSA-h2xv-5x52-7qvw Published Today

75

High Risk

This Affects:

JAVAhttp4s-core_3
0.23.20 - 0.23.36
Fixed in 0.23.37
Are you affected? Scan for Free

TL;DR

The WebSocket frame defragmenter reassembles fragmented messages but only caps the accumulated byte size, never the number of fragments, and re-folds every previously buffered fragment each time a new one arrives. A peer that streams many zero length continuation frames (roughly 600 KB of wire data, about 100,000 empty frames) drives quadratic work over the growing fragment buffer, pinning a service thread and exhausting CPU. The fix caps the fragment count with a TooManyFragments limit and stops re-processing already buffered fragments.

Who does this affect?

You are affected if you are using a version that falls within the vulnerable range and your service accepts WebSocket connections.

Background info

http4s-core_3 is vulnerable to Denial of Service (DoS) in versions 0.23.20 - 0.23.36.

How to fix this

Upgrade the org.http4s:http4s-core_3 library to the patch version.

Are You Affected?

Connect your repositories to instantly see whether vulnerable or malicious packages exist in your codebase.

Free. No credit card required.

Aikido Platform