PT-2026-56603 · Libp2P · Js-Libp2P

Published 2026-07-08 · Updated 2026-07-08 · CVE-2026-49866

Mitre

CVSS v3.1

7.5

High

Base vector

AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

libp2p is a JavaScript Implementation of libp2p networking stack. Prior to 16.0.0, @libp2p/gossipsub defaultDecodeRpcLimits set maxIhaveMessageIDs and maxIwantMessageIDs to Infinity, allowing oversized IHAVE and IWANT control message arrays in message/decodeRpc.ts and gossipsub.ts to synchronously iterate roughly 180,000 message IDs per 4 MB frame and block the Node.js event loop. This issue is fixed in version 16.0.0.

Fix

Allocation of Resources Without Limits

Weakness Enumeration

CWE-770

Related Identifiers

CVE-2026-49866

Affected Products

Js-Libp2P

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2026-49866 · Security Note
• https://github.com/libp2p/js-libp2p/pull/3520 · Note
• https://github.com/libp2p/js-libp2p/security/advisories/GHSA-cwc9-cp4j-mcvv · Note
• https://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.0 · Note
• https://github.com/libp2p/js-libp2p/commit/773dd80ded24dbd6b19e675c89fd2f3b45f2d899 · Note