CVE-2026-49866
HIGHlibp2p: CPU DoS via oversized IHAVE and IWANT control message arrays
Title source: cnaDescription
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.
References (4)
Core 4
Core References
X_Refsource_Confirm x_refsource_confirm
https://github.com/libp2p/js-libp2p/security/advisories/GHSA-cwc9-cp4j-mcvv
X_Refsource_Misc x_refsource_misc
https://github.com/libp2p/js-libp2p/pull/3520
X_Refsource_Misc x_refsource_misc
https://github.com/libp2p/js-libp2p/commit/773dd80ded24dbd6b19e675c89fd2f3b45f2d899
X_Refsource_Misc x_refsource_misc
https://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.0
Scores
CVSS v3
7.5
EPSS
0.0045
EPSS Percentile
36.4%
Attack Vector
NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CISA SSVC
Vulnrichment
Exploitation
none
Automatable
yes
Technical Impact
partial
Details
CWE
CWE-770
Status
published
Products (2)
libp2p/gossipsub
0 - 16.0.0npm
libp2p/js-libp2p
< 16.0.0
Published
Jul 08, 2026
Tracked Since
Jul 09, 2026