CVE-2026-49866
Published:July 08, 2026
Updated:August 04, 2026
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.
Affected Packages
https://github.com/libp2p/js-libp2p.git (GITHUB):
Affected version(s) >=auto-tls-v1.0.0 <16.0.0Fix Suggestion:
Update to version 16.0.0@libp2p/gossipsub (NPM):
Affected version(s) >=14.1.1 <16.0.0Fix Suggestion:
Update to version 16.0.0@libp2p/gossipsub (NPM):
Affected version(s) >=14.1.1 <16.0.0Fix Suggestion:
Update to version 16.0.0Related Resources (7)
Do you need more information?
Contact UsCVSS v4
Base Score:
8.7
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
NONE
User Interaction
NONE
Vulnerable System Confidentiality
NONE
Vulnerable System Integrity
NONE
Vulnerable System Availability
HIGH
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.5
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
NONE
Integrity
NONE
Availability
HIGH
Weakness Type (CWE)
EPSS
Base Score:
0.44