« Volver al listado

CVE-2026-74937

Estado: AnalizadaAlta (8.8)—

Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.

CVSS

Probabilidad de explotación (EPSS)

EPSS (Exploit Prediction Scoring System, de FIRST) estima la probabilidad de que una vulnerabilidad sea explotada en 30 días. Complementa a CVSS (impacto) y a CISA KEV (explotación confirmada).

🎯 Técnicas ATT&CK

Cómo se explota esta vulnerabilidad y qué consigue el atacante, en el lenguaje de MITRE ATT&CK.

CWE-416 (use-after-free) en componente JavaScript de Firefox/Thunderbird con UI:R (requiere interacción del usuario al abrir archivo/enlace). Permite ejecución arbitraria de código en el contexto del navegador.

Inferido por nuestro agente de análisis a partir de la descripción oficial, el vector CVSS y la CWE, y comprobado por un supervisor. Puede contener errores.

🛡️ Mitigaciones ATT&CK que cubren estas técnicas

Restrict Web-Based ContentPrivileged Account ManagementLimit Software InstallationExecution PreventionBehavior Prevention on EndpointDisable or Remove Feature or Program

Tecnologías afectadas (2)

Mozilla — FirefoxMozilla — Thunderbird

CWE

Referencias

JSON original (NVD)

Mostrar
{
  "id": "CVE-2026-74937",
  "cveTags": [],
  "metrics": {
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2026-74937",
          "role": "CISA Coordinator",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "version": "2.0.3",
          "timestamp": "2026-08-18T19:20:21.024380Z"
        }
      }
    ],
    "cvssMetricV31": [
      {
        "type": "Secondary",
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "cvssData": {
          "scope": "UNCHANGED",
          "version": "3.1",
          "baseScore": 8.8,
          "attackVector": "NETWORK",
          "baseSeverity": "HIGH",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H",
          "integrityImpact": "HIGH",
          "userInteraction": "REQUIRED",
          "attackComplexity": "LOW",
          "availabilityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "confidentialityImpact": "HIGH"
        },
        "impactScore": 5.9,
        "exploitabilityScore": 2.8
      }
    ]
  },
  "affected": [
    {
      "source": "security@mozilla.org",
      "affectedData": [
        {
          "vendor": "Mozilla",
          "product": "Firefox",
          "versions": [
            {
              "status": "unaffected",
              "version": "153.1",
              "versionType": "rpm",
              "lessThanOrEqual": "153.*"
            },
            {
              "status": "unaffected",
              "version": "154",
              "versionType": "rpm",
              "lessThanOrEqual": "*"
            }
          ]
        },
        {
          "vendor": "Mozilla",
          "product": "Thunderbird",
          "versions": [
            {
              "status": "unaffected",
              "version": "153.1",
              "versionType": "rpm",
              "lessThanOrEqual": "153.*"
            },
            {
              "status": "unaffected",
              "version": "154",
              "versionType": "rpm",
              "lessThanOrEqual": "*"
            }
          ]
        }
      ]
    }
  ],
  "published": "2026-08-18T13:17:29.950",
  "references": [
    {
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2053337",
      "tags": [
        "Permissions Required"
      ],
      "source": "security@mozilla.org"
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-74/",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@mozilla.org"
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-77/",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@mozilla.org"
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-78/",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@mozilla.org"
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-80/",
      "tags": [
        "Vendor Advisory"
      ],
      "source": "security@mozilla.org"
    }
  ],
  "vulnStatus": "Analyzed",
  "weaknesses": [
    {
      "type": "Secondary",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "description": [
        {
          "lang": "en",
          "value": "CWE-416"
        }
      ]
    }
  ],
  "descriptions": [
    {
      "lang": "en",
      "value": "Use-after-free in the JavaScript: GC component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1."
    }
  ],
  "lastModified": "2026-08-19T00:58:37.713",
  "configurations": [
    {
      "nodes": [
        {
          "negate": false,
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:esr:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "21D97347-77F7-440B-9B0D-B97FD4BB38C6",
              "versionEndExcluding": "153.1.0"
            },
            {
              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:-:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "F16EF6DF-DA4B-43C3-A378-66A55A822738",
              "versionEndExcluding": "154.0.0"
            },
            {
              "criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "FD0B7622-C417-4F68-A7C0-BD9E897997A1",
              "versionEndExcluding": "153.1.0"
            },
            {
              "criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:-:*:*:*",
              "vulnerable": true,
              "matchCriteriaId": "D5E5AB38-17E4-4A6E-A147-7B00E988266C",
              "versionEndExcluding": "154.0"
            }
          ],
          "operator": "OR"
        }
      ]
    }
  ],
  "sourceIdentifier": "security@mozilla.org"
}