CVE-2026-86040

Vulnerability Description

libp2p is a JavaScript implementation of the libp2p networking stack. Prior to 11.0.26, @libp2p/floodsub accepts unauthenticated RPC frames on /floodsub/1.0.0 through PeerStreams.attachInboundStream in packages/floodsub/src/peer-streams.ts without protobuf element limits, then processRpc and processRpcSubOpt in packages/floodsub/src/floodsub.ts synchronously process the subscriptions array without a per-frame cap. A single bounded-size frame can decode into millions of empty subscription entries that block the event loop, while hundreds of thousands of unique-topic SUBSCRIBE entries allocate PeerSet objects in this.topics that are not removed after peer removal or stop. Empty entries cause CPU exhaustion but do not grow this.topics; persistent memory growth requires unique topics. The subscription path bypasses message signature validation and the message-only processing queue, allowing a remote peer to cause sustained CPU denial of service, memory exhaustion, out-of-memory termination, and node unavailability. The issue is fixed in version 11.0.26.

CVSS Score

Related Weaknesses (CWE)

References

• https://github.com/libp2p/js-libp2p/commit/fb9e8a76e9ac75924928fae4ce11d00f68320
• https://github.com/libp2p/js-libp2p/pull/3568
• https://github.com/libp2p/js-libp2p/releases/tag/floodsub-v11.0.26
• https://github.com/libp2p/js-libp2p/security/advisories/GHSA-cvfg-hcf3-ggwv