CVE-2026-49866

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/libp2p/js-libp2p/commit/773dd80ded24dbd6b19e675c89fd2f3b45f2d899
https://github.com/libp2p/js-libp2p/pull/3520
https://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.0
https://github.com/libp2p/js-libp2p/security/advisories/GHSA-cwc9-cp4j-mcvv

Configurations

No configuration.

History

No history.

Information

Published : 2026-07-08 21:16

Updated : 2026-07-10 19:10

NVD link : CVE-2026-49866

Mitre link : CVE-2026-49866

CVE.ORG link : CVE-2026-49866

JSON object : View

Products Affected

No product.

CWE

CWE-770

Allocation of Resources Without Limits or Throttling

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