Quick answers
- Is CVE-2026-77384 exploited in the wild?
- No. Junglewise Threat Intelligence has no report of CVE-2026-77384 being exploited in the wild.
- How severe is CVE-2026-77384?
- High severity, with a CVSS score of 7.5, published 24 August 2026.
- Which products and versions are affected?
- Libp2p Circuit-Relay-V2 before 4.2.9.
- Is there a fix for CVE-2026-77384?
- A patch was published on 2026-07-19: version 4.2.9 released Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
- How is CVE-2026-77384 attacked?
- It is attacked over the network.
- Am I affected by CVE-2026-77384?
- Check whether you run Libp2p Circuit-Relay-V2 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.
Technical details
The vulnerability is a resource leak in the reservation refresh path within reservation-store.ts. The code reuses the same retimeableSignal object but unconditionally registers an additional abort listener on every refresh request, causing listeners and closures to accumulate without bound. A remote peer can exploit this by repeatedly sending valid RESERVE requests for the same reservation. No authentication or special privileges are required; the attack is network-accessible. The result is memory exhaustion and denial of service on circuit-relay-v2 relay servers. The vulnerability is fixed in version 4.2.9 by attaching the abort listener only once when the signal is created, rather than on every refresh.
Affected products
- libp2p circuit-relay-v2 before 4.2.9
Timeline
- 2026-08-24: disclosed
- 2026-07-19: patched: version 4.2.9 released