# CVE-2026-77384 — libp2p js-libp2p

> As of 2026-08-24, CVE-2026-77384 is a HIGH-severity vulnerability in libp2p js-libp2p, CVSS v3.1 7.5, EPSS 0.3% (26.3th percentile). No Threadlinqs-tracked threat campaign has been attributed to CVE-2026-77384 as of 2026-08-24; the identifier is re-checked against the Threadlinqs threat corpus on every daily ingest.

**Last updated:** 2026-08-24

## What is CVE-2026-77384?

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.

The record classifies CVE-2026-77384 under weakness classes [CWE-400](https://intel.threadlinqs.com/cwe/CWE-400), [CWE-772](https://cwe.mitre.org/data/definitions/772.html). Its CVSS v3 base vector states that the flaw is reachable remotely over the network, needs no prior authentication, needs no user interaction, and has high impact on availability. 1 affected-product entry is recorded, across 1 vendor, listed below. The identifier was first published 42 days ago.

## Severity and exploitation probability

- **CVSS v3.1 base score:** 7.5 — HIGH (`CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H`)
- **EPSS (FIRST):** 0.3% probability of exploitation in the next 30 days, higher than 26.3% of all scored CVEs
- **CISA KEV:** Not listed in the CISA Known Exploited Vulnerabilities catalog
- **Threadlinqs priority:** 4.8/10 — a Threadlinqs composite of the CVSS base score, the EPSS percentile and public exploit availability
- **Published:** 2026-08-24

## Is CVE-2026-77384 being exploited?

It currently carries a trending score of 36 in the Threadlinqs vulnerability feed.

## Affected products and versions

- **libp2p**: js-libp2p

## How to fix CVE-2026-77384

No vendor patch reference has been recorded for CVE-2026-77384 in the tracked sources. Follow the references below for a fix, and treat the products listed above as exposed until the vendor states otherwise.

## Threat activity tracking CVE-2026-77384

No threat campaign in the Threadlinqs corpus currently references CVE-2026-77384, in its CVE list or as an indicator. The linkage is recomputed from the live corpus on every daily ingest, so this section fills in as soon as a tracked campaign cites the identifier.

## Sources

Enriched from CVE.org, NVD, FIRST EPSS. Last verified by Threadlinqs on 2026-08-25. This product uses the NVD API but is not endorsed or certified by the NVD.

**Vendor advisory and patch**

- [github.com](https://github.com/libp2p/js-libp2p/security/advisories/GHSA-x787-gh7p-hmq7)

**Other references**

- [github.com](https://github.com/libp2p/js-libp2p/commit/4bb8fbe8d3f3590e4af51a1f5f7de56fffa5804d)
- [github.com (circuit relay v2 v4.2)](https://github.com/libp2p/js-libp2p/releases/tag/circuit-relay-v2-v4.2.9)

Canonical: https://intel.threadlinqs.com/cve/CVE-2026-77384
Full detection coverage and IOCs for threats exploiting CVE-2026-77384 via the Threadlinqs MCP server (Purple tier): https://intel.threadlinqs.com/mcp