FKIE_CVE-2026-49866

Vulnerability from fkie_nvd - Published: 2026-07-08 21:16 - Updated: 2026-07-10 19:10
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Summary
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
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/commit/773dd80ded24dbd6b19e675c89fd2f3b45f2d899
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/pull/3520
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.0
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/security/advisories/GHSA-cwc9-cp4j-mcvv
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "js-libp2p",
          "vendor": "libp2p",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 16.0.0"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "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."
    }
  ],
  "id": "CVE-2026-49866",
  "lastModified": "2026-07-10T19:10:59.333",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6,
        "source": "security-advisories@github.com",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-49866",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-07-09T14:37:59.412018Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-07-08T21:16:49.137",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/commit/773dd80ded24dbd6b19e675c89fd2f3b45f2d899"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/pull/3520"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.0"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/security/advisories/GHSA-cwc9-cp4j-mcvv"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Deferred",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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