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FKIE_CVE-2026-86038

Vulnerability from fkie_nvd - Published: 2026-09-17 16:18 - Updated: 2026-09-17 18:17
Severity
7.5 (High) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N
Summary
libp2p is a JavaScript implementation of the libp2p networking stack. From 15.0.0 until 16.0.5, @libp2p/gossipsub uses the default StrictSign policy in packages/gossipsub/src/utils/buildRawMessage.ts, where validateToRawMessage verifies a signature with attacker-controlled msg.key but skips binding that key to msg.from when the claimed author is an RSA peer ID that does not inline a public key. An unauthenticated attacker can place a victim RSA peer ID in msg.from, sign the message with the attacker's private key, and supply the attacker's public key in msg.key, causing the message to be accepted and propagated as authored by the victim. Applications that trust message.from for validators, authorization, accounting, moderation, reputation, or audit logging can process attacker-controlled data under false origin attribution. The issue is fixed in version 16.0.5.
References
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/commit/cec2b1f349d130065e561349a0336a239528267f
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/pull/3569
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.5
security-advisories@github.comhttps://github.com/libp2p/js-libp2p/security/advisories/GHSA-c3gv-825q-fvmp
134c704f-9b21-4f2e-91b3-4a467353bcc0https://github.com/libp2p/js-libp2p/security/advisories/GHSA-c3gv-825q-fvmp
Impacted products
Vendor Product Version
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "js-libp2p",
          "vendor": "libp2p",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 15.0.0, \u003c 16.0.5"
            }
          ]
        }
      ],
      "source": "security-advisories@github.com"
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "libp2p is a JavaScript implementation of the libp2p networking stack. From 15.0.0 until 16.0.5, @libp2p/gossipsub uses the default StrictSign policy in packages/gossipsub/src/utils/buildRawMessage.ts, where validateToRawMessage verifies a signature with attacker-controlled msg.key but skips binding that key to msg.from when the claimed author is an RSA peer ID that does not inline a public key. An unauthenticated attacker can place a victim RSA peer ID in msg.from, sign the message with the attacker\u0027s private key, and supply the attacker\u0027s public key in msg.key, causing the message to be accepted and propagated as authored by the victim. Applications that trust message.from for validators, authorization, accounting, moderation, reputation, or audit logging can process attacker-controlled data under false origin attribution. The issue is fixed in version 16.0.5."
    }
  ],
  "id": "CVE-2026-86038",
  "lastModified": "2026-09-17T18:17:12.203",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "LOW",
          "attackVector": "NETWORK",
          "availabilityImpact": "NONE",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "NONE",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N",
          "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-2026-86038",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2026-09-17T17:24:10.344562Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2026-09-17T16:18:16.927",
  "references": [
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/commit/cec2b1f349d130065e561349a0336a239528267f"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/pull/3569"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/releases/tag/gossipsub-v16.0.5"
    },
    {
      "source": "security-advisories@github.com",
      "url": "https://github.com/libp2p/js-libp2p/security/advisories/GHSA-c3gv-825q-fvmp"
    },
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "url": "https://github.com/libp2p/js-libp2p/security/advisories/GHSA-c3gv-825q-fvmp"
    }
  ],
  "sourceIdentifier": "security-advisories@github.com",
  "vulnStatus": "Received",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-345"
        },
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ],
      "source": "security-advisories@github.com",
      "type": "Secondary"
    }
  ]
}



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