libp2p up to 6.0.27 STUN Listener stun-listener.ts DirectRTCPeerConnection.setLocalDescription ufrag resource consumption

Summaryinfo

A vulnerability was found in libp2p up to 6.0.27. It has been declared as problematic. This impacts the function DirectRTCPeerConnection.setLocalDescription of the file packages/transport-webrtc/src/private-to-public/utils/stun-listener.ts of the component STUN Listener. Executing a manipulation of the argument ufrag can lead to resource consumption. This vulnerability appears as CVE-2026-103936. The attack may be performed from remote. There is no available exploit. It is recommended to upgrade the affected component.

Detailsinfo

A vulnerability was found in libp2p up to 6.0.27. It has been declared as problematic. This vulnerability affects the function DirectRTCPeerConnection.setLocalDescription of the file packages/transport-webrtc/src/private-to-public/utils/stun-listener.ts of the component STUN Listener. The manipulation of the argument ufrag with an unknown input leads to a resource consumption vulnerability. The CWE definition for the vulnerability is CWE-400. The product does not properly control the allocation and maintenance of a limited resource, thereby enabling an actor to influence the amount of resources consumed, eventually leading to the exhaustion of available resources. As an impact it is known to affect availability. CVE summarizes:

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.

The advisory is shared for download at github.com. This vulnerability was named CVE-2026-103936 since 10/01/2026. The exploitation appears to be easy. The attack can be initiated remotely. No form of authentication is required for a successful exploitation. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1499.

Upgrading to version 6.0.28 eliminates this vulnerability.

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Productinfo

Name

• libp2p

Version

• 6.0.0
• 6.0.1
• 6.0.2
• 6.0.3
• 6.0.4
• 6.0.5
• 6.0.6
• 6.0.7
• 6.0.8
• 6.0.9
• 6.0.10
• 6.0.11
• 6.0.12
• 6.0.13
• 6.0.14
• 6.0.15
• 6.0.16
• 6.0.17
• 6.0.18
• 6.0.19
• 6.0.20
• 6.0.21
• 6.0.22
• 6.0.23
• 6.0.24
• 6.0.25
• 6.0.26
• 6.0.27

CPE 2.3info

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CPE 2.2info

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