Vulnerability · Published Aug 24, 2026 · Assigned by GitHub_M

CVE-2026-77384libp2p: Circuit relay v2 server reservation refresh leaks abort listeners and allows remote resource exhaustion

High 7.5

In plain English

A high-severity uncontrolled resource consumption in js-libp2p from libp2p. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 49% of all known vulnerabilities).

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.6%top 50.6% of all CVEs

Exploited in the wildNo reportsCISA SSVC: poc

Attack toolingNoneno public tooling known

Official description

libp2p is a JavaScript implementation of the libp2p networking stack. Prior to version 4.2.9, the reservation refresh path in reservation-store.ts reuses the same retimeableSignal but unconditionally registers another abort listener on every refresh. As a result, a remote peer can repeatedly send valid RESERVE requests for the same reservation, causing unbounded listener and closure growth in @libp2p/circuit-relay-v2 relay servers and leading to denial of service. This issue is fixed in version 4.2.9.

Affected products (as reported)

Vendor	Product	Versions
libp2p	js-libp2p	>= 2.1.5, < 4.2.9

Weakness: CWE-400, CWE-772 · 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-x787-gh7p-hmq7 x_refsource_CONFIRM
https://github.com/libp2p/js-libp2p/commit/4bb8fbe8d3f3590e4af51a1f5f7de56fffa5804d x_refsource_MISC
https://github.com/libp2p/js-libp2p/releases/tag/circuit-relay-v2-v4.2.9 x_refsource_MISC