CVE-2026-41431

{
  "id": "CVE-2026-41431",
  "sourceIdentifier": "[email protected]",
  "published": "2026-05-11T18:16:34.280",
  "lastModified": "2026-10-26T18:10:00.173",
  "vulnStatus": "Deferred",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Zen is a firefox-based browser. Prior to 1.19.9b, Zen Browser ships a Mozilla Application Resource (MAR) updater (org.mozilla.updater) that has had all MAR signature verification stripped from the Firefox codebase it was forked from. The MAR files served to users contain zero cryptographic signatures, and the updater binary contains zero cryptographic verification code. This eliminates the defense-in-depth that MAR signing provides. If the update server or GitHub release pipeline is compromised, arbitrary unsigned code can be delivered to all Zen users via the auto-update mechanism. This vulnerability is fixed in 1.19.9b."
    },
    {
      "lang": "es",
      "value": "Zen es un navegador basado en Firefox. Antes de la 1.19.9b, Zen Browser incluye un actualizador de Recursos de Aplicación de Mozilla (MAR) (org.mozilla.updater) al que se le había eliminado toda la verificación de firma MAR del código base de Firefox del que se bifurcó. Los archivos MAR servidos a los usuarios contienen cero firmas criptográficas, y el binario del actualizador contiene cero código de verificación criptográfica. Esto elimina la defensa en profundidad que proporciona la firma MAR. Si el servidor de actualizaciones o el pipeline de lanzamiento de GitHub se ve comprometido, código arbitrario sin firmar puede ser entregado a todos los usuarios de Zen a través del mecanismo de autoactualización. Esta vulnerabilidad está corregida en la 1.19.9b."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "zen-browser",
          "product": "desktop",
          "versions": [
            {
              "version": "< 1.19.9b",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:H/UI:N/S:C/C:H/I:H/A:H",
          "baseScore": 8.0,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "HIGH",
          "privilegesRequired": "HIGH",
          "userInteraction": "NONE",
          "scope": "CHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 1.3,
        "impactScore": 6.0
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-05-11T18:31:13.968267Z",
          "id": "CVE-2026-41431",
          "options": [
            {
              "exploitation": "poc"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-347"
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/zen-browser/desktop/commit/270db6d6713d2c6c14d9df0b4bc7662843d3d54e",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/zen-browser/desktop/security/advisories/GHSA-qpj9-m8jc-mw6q",
      "source": "[email protected]"
    },
    {
      "url": "https://github.com/zen-browser/desktop/security/advisories/GHSA-qpj9-m8jc-mw6q",
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0"
    }
  ]
}