CVE-2026-63384

{
  "id": "CVE-2026-63384",
  "sourceIdentifier": "[email protected]",
  "published": "2026-08-20T18:16:36.367",
  "lastModified": "2026-10-26T10:10:00.140",
  "vulnStatus": "Awaiting Analysis",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Libevent is an event notification library. Prior to 2.1.13 and 2.2.2-alpha, libevent has an incorrect integer conversion in event_tagging.c when evtag_unmarshal_header uses evtag_decode_int to decode an attacker-controlled uint32 payload length and returns it as a signed int. Values above INT_MAX become negative or truncated, and evtag_unmarshal_string can use the converted value in allocation sizing, producing a wrapped large allocation request and denial of service. This issue is fixed in versions 2.1.13 and 2.2.2-alpha."
    },
    {
      "lang": "es",
      "value": "Libevent es una biblioteca de notificación de eventos. Antes de las versiones 2.1.13 y 2.2.2-alpha, libevent tiene una conversión de entero incorrecta en event_tagging.c cuando evtag_unmarshal_header usa evtag_decode_int para decodificar una longitud de carga útil uint32 controlada por el atacante y la devuelve como un entero con signo. Valores superiores a INT_MAX se vuelven negativos o truncados, y evtag_unmarshal_string puede usar el valor convertido en el dimensionamiento de la asignación, produciendo una solicitud de asignación grande envuelta y denegación de servicio. Este problema está corregido en las versiones 2.1.13 y 2.2.2-alpha."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "libevent",
          "product": "libevent",
          "versions": [
            {
              "version": ">= 2.2.0-alpha, < 2.2.2-alpha",
              "status": "affected"
            },
            {
              "version": "< 2.1.13",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV40": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "4.0",
          "vectorString": "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
          "baseScore": 8.7,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "attackRequirements": "NONE",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "vulnConfidentialityImpact": "NONE",
          "vulnIntegrityImpact": "NONE",
          "vulnAvailabilityImpact": "HIGH",
          "subConfidentialityImpact": "NONE",
          "subIntegrityImpact": "NONE",
          "subAvailabilityImpact": "NONE",
          "exploitMaturity": "NOT_DEFINED",
          "confidentialityRequirement": "NOT_DEFINED",
          "integrityRequirement": "NOT_DEFINED",
          "availabilityRequirement": "NOT_DEFINED",
          "modifiedAttackVector": "NOT_DEFINED",
          "modifiedAttackComplexity": "NOT_DEFINED",
          "modifiedAttackRequirements": "NOT_DEFINED",
          "modifiedPrivilegesRequired": "NOT_DEFINED",
          "modifiedUserInteraction": "NOT_DEFINED",
          "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
          "modifiedVulnIntegrityImpact": "NOT_DEFINED",
          "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
          "modifiedSubConfidentialityImpact": "NOT_DEFINED",
          "modifiedSubIntegrityImpact": "NOT_DEFINED",
          "modifiedSubAvailabilityImpact": "NOT_DEFINED",
          "Safety": "NOT_DEFINED",
          "Automatable": "NOT_DEFINED",
          "Recovery": "NOT_DEFINED",
          "valueDensity": "NOT_DEFINED",
          "vulnerabilityResponseEffort": "NOT_DEFINED",
          "providerUrgency": "NOT_DEFINED"
        }
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-08-20T19:50:07.634809Z",
          "id": "CVE-2026-63384",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-190"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/libevent/libevent/commit/109c16499282959d70f56ec3baf4c8b1e6646bda",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/libevent/libevent/commit/5e3c6ebe342b34c5a9bcf48e9a32ad6708b9c416",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/libevent/libevent/releases/tag/release-2.1.13-stable",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/libevent/libevent/releases/tag/release-2.2.2-alpha",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/libevent/libevent/security/advisories/GHSA-45c6-qx49-89m8",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}