{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-48516",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-06-23T12:28:14.996422Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-06-23T12:28:23.531Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "MessagePack-CSharp",
          "vendor": "MessagePack-CSharp",
          "versions": [
            {
              "status": "affected",
              "version": "\u003e= 3.0, \u003c 3.1.7"
            },
            {
              "status": "affected",
              "version": "\u003c 2.5.301"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, InterfaceLookupFormatter\u003cTKey,TElement\u003e constructs an internal Dictionary\u003cTKey, IGrouping\u003cTKey,TElement\u003e\u003e with the default equality comparer instead of the security-aware comparer supplied by options.Security.GetEqualityComparer\u003cTKey\u003e(). This formatter omission allows hash-collision CPU denial of service against ILookup\u003cTKey,TElement\u003e even when the application has opted into the untrusted-data security posture This vulnerability is fixed in 2.5.301 and 3.1.7."
        }
      ],
      "metrics": [
        {
          "cvssV4_0": {
            "attackComplexity": "HIGH",
            "attackRequirements": "PRESENT",
            "attackVector": "NETWORK",
            "baseScore": 6.3,
            "baseSeverity": "MEDIUM",
            "privilegesRequired": "NONE",
            "subAvailabilityImpact": "NONE",
            "subConfidentialityImpact": "NONE",
            "subIntegrityImpact": "NONE",
            "userInteraction": "NONE",
            "vectorString": "CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N",
            "version": "4.0",
            "vulnAvailabilityImpact": "LOW",
            "vulnConfidentialityImpact": "NONE",
            "vulnIntegrityImpact": "NONE"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-407",
              "description": "CWE-407: Inefficient Algorithmic Complexity",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-06-25T15:54:33.529Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-q2h6-ghwm-5qm8",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-q2h6-ghwm-5qm8"
        }
      ],
      "source": {
        "advisory": "GHSA-q2h6-ghwm-5qm8",
        "discovery": "UNKNOWN"
      },
      "title": "MessagePack-CSharp: InterfaceLookupFormatter bypasses collision-resistant comparer settings"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-48516",
    "datePublished": "2026-06-22T21:09:51.787Z",
    "dateReserved": "2026-05-21T16:18:10.619Z",
    "dateUpdated": "2026-06-25T15:54:33.529Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-48516\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"no\"}, {\"Technical Impact\": \"partial\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-06-23T12:28:14.996422Z\"}}}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-06-23T12:28:19.914Z\"}}], \"cna\": {\"title\": \"MessagePack-CSharp: InterfaceLookupFormatter bypasses collision-resistant comparer settings\", \"source\": {\"advisory\": \"GHSA-q2h6-ghwm-5qm8\", \"discovery\": \"UNKNOWN\"}, \"metrics\": [{\"cvssV4_0\": {\"version\": \"4.0\", \"baseScore\": 6.3, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"MEDIUM\", \"vectorString\": \"CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"HIGH\", \"attackRequirements\": \"PRESENT\", \"privilegesRequired\": \"NONE\", \"subIntegrityImpact\": \"NONE\", \"vulnIntegrityImpact\": \"NONE\", \"subAvailabilityImpact\": \"NONE\", \"vulnAvailabilityImpact\": \"LOW\", \"subConfidentialityImpact\": \"NONE\", \"vulnConfidentialityImpact\": \"NONE\"}}], \"affected\": [{\"vendor\": \"MessagePack-CSharp\", \"product\": \"MessagePack-CSharp\", \"versions\": [{\"status\": \"affected\", \"version\": \"\u003e= 3.0, \u003c 3.1.7\"}, {\"status\": \"affected\", \"version\": \"\u003c 2.5.301\"}]}], \"references\": [{\"url\": \"https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-q2h6-ghwm-5qm8\", \"name\": \"https://github.com/MessagePack-CSharp/MessagePack-CSharp/security/advisories/GHSA-q2h6-ghwm-5qm8\", \"tags\": [\"x_refsource_CONFIRM\"]}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"MessagePack for C# is a MessagePack serializer for C#. Prior to 2.5.301 and 3.1.7, InterfaceLookupFormatter\u003cTKey,TElement\u003e constructs an internal Dictionary\u003cTKey, IGrouping\u003cTKey,TElement\u003e\u003e with the default equality comparer instead of the security-aware comparer supplied by options.Security.GetEqualityComparer\u003cTKey\u003e(). This formatter omission allows hash-collision CPU denial of service against ILookup\u003cTKey,TElement\u003e even when the application has opted into the untrusted-data security posture This vulnerability is fixed in 2.5.301 and 3.1.7.\"}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-407\", \"description\": \"CWE-407: Inefficient Algorithmic Complexity\"}]}], \"providerMetadata\": {\"orgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"shortName\": \"GitHub_M\", \"dateUpdated\": \"2026-06-25T15:54:33.529Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-48516\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-06-25T15:54:33.529Z\", \"dateReserved\": \"2026-05-21T16:18:10.619Z\", \"assignerOrgId\": \"a0819718-46f1-4df5-94e2-005712e83aaa\", \"datePublished\": \"2026-06-22T21:09:51.787Z\", \"assignerShortName\": \"GitHub_M\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}