{"schemaVersion":3,"id":"CVE-2026-49866","aliases":["GHSA-cwc9-cp4j-mcvv"],"status":"published","duplicateOf":null,"title":null,"description":"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. 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