CVE-2026-43678

Description

An unauthenticated remote peer can crash any NIOWebSocket-based server (including Vapor and Hummingbird) with a single 11-byte frame sent after a completed WebSocket handshake, dropping all active connections until the process restarts. This vulnerability is addressed in swift-nio version 2.101.0.

CVSS Vector

References

• https://github.com/apple/swift-nio/security/advisories/GHSA-qcc5-f287-vgmq