Vulnerability · Published Oct 15, 2026 · Assigned by GitHub_M
CVE-2026-103936libp2p: Single pre-auth STUN packet terminates `@libp2p/webrtc` WebRTC-direct Node.js listeners
High 7.5
In plain English
A high-severity security flaw in js-libp2p from libp2p. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 44% of all known vulnerabilities).
Official description
libp2p is a JavaScript implementation of the libp2p networking stack. Prior to 6.0.28, the @libp2p/webrtc webRTCDirect() Node.js listener processes unauthenticated STUN Binding Requests before PeerId authentication, Noise, muxing, protocol negotiation, connection creation, or connection-manager admission. The listener in packages/transport-webrtc/src/private-to-public/utils/stun-listener.ts forwards the packet-controlled request.ufrag into DirectRTCPeerConnection.setLocalDescription, where the value is reused as an ICE password without validating its required length and character set. A short credential causes node-datachannel or libdatachannel to raise an uncaught native invalid_argument and abort the process with SIGABRT, allowing a single remote UDP packet to deny service. The confirmed impact is process termination only, with no demonstrated memory corruption, code execution, browser impact, confidentiality impact, integrity impact, or connection-limit bypass. This issue is fixed in version 6.0.28.
Affected products (as reported)
Weakness: CWE-248, CWE-755 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
References
- https://github.com/libp2p/js-libp2p/security/advisories/GHSA-x3m2-6mg8-vj7f x_refsource_CONFIRM
- https://github.com/libp2p/js-libp2p/pull/3584 x_refsource_MISC
- https://github.com/libp2p/js-libp2p/commit/68794c8e2e67d5f38da59e379dc051b2789e46f6 x_refsource_MISC
- https://github.com/libp2p/js-libp2p/releases/tag/webrtc-v6.0.28 x_refsource_MISC