FKIE_CVE-2025-6435

Vulnerability from fkie_nvd - Published: 2025-06-24 13:15 - Updated: 2026-09-30 18:10
Severity
8.1 (High) - CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
Summary
If a user saved a response from the Network tab in Devtools using the Save As context menu option, that file may not have been saved with the `.download` file extension. This could have led to the user inadvertently running a malicious executable. This vulnerability was fixed in Firefox 140 and Thunderbird 140.
References
security@mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=1950056Permissions Required
security@mozilla.orghttps://bugzilla.mozilla.org/show_bug.cgi?id=1961777Permissions Required
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2025-51/Vendor Advisory
security@mozilla.orghttps://www.mozilla.org/security/advisories/mfsa2025-54/Vendor Advisory
Impacted products
Vendor Product Version
mozilla firefox *
mozilla thunderbird *
To clipboard 

{
  "affected": [
    {
      "affectedData": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "140",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "140",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "source": "security@mozilla.org"
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "cpeMatch": [
            {
              "criteria": "cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "6BD96DBF-567C-4E36-844D-B25A4E22CE40",
              "versionEndExcluding": "140.0",
              "vulnerable": true
            },
            {
              "criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:*:*:*:*",
              "matchCriteriaId": "EE6112E1-F482-4916-BA5E-68868793540F",
              "versionEndExcluding": "140.0",
              "vulnerable": true
            }
          ],
          "negate": false,
          "operator": "OR"
        }
      ]
    }
  ],
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "If a user saved a response from the Network tab in Devtools using the Save As context menu option, that file may not have been saved with the `.download` file extension. This could have led to the user inadvertently running a malicious executable. This vulnerability was fixed in Firefox 140 and Thunderbird 140."
    },
    {
      "lang": "es",
      "value": "Si un usuario guard\u00f3 una respuesta desde la pesta\u00f1a Red en DevTools mediante la opci\u00f3n Guardar como del men\u00fa contextual, es posible que el archivo no se haya guardado con la extensi\u00f3n \u0027.download\u0027. Esto podr\u00eda haber provocado que el usuario ejecutara accidentalmente un archivo malicioso. Esta vulnerabilidad afecta a Firefox anterior a la versi\u00f3n 140."
    }
  ],
  "id": "CVE-2025-6435",
  "lastModified": "2026-09-30T18:10:00.190",
  "metrics": {
    "cvssMetricV31": [
      {
        "cvssData": {
          "attackComplexity": "HIGH",
          "attackVector": "NETWORK",
          "availabilityImpact": "HIGH",
          "baseScore": 8.1,
          "baseSeverity": "HIGH",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "privilegesRequired": "NONE",
          "scope": "UNCHANGED",
          "userInteraction": "NONE",
          "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "version": "3.1"
        },
        "exploitabilityScore": 2.2,
        "impactScore": 5.9,
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary"
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "id": "CVE-2025-6435",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "timestamp": "2025-06-24T13:37:09.229042Z",
          "version": "2.0.3"
        }
      }
    ]
  },
  "published": "2025-06-24T13:15:24.560",
  "references": [
    {
      "source": "security@mozilla.org",
      "tags": [
        "Permissions Required"
      ],
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1950056"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
        "Permissions Required"
      ],
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=1961777"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2025-51/"
    },
    {
      "source": "security@mozilla.org",
      "tags": [
        "Vendor Advisory"
      ],
      "url": "https://www.mozilla.org/security/advisories/mfsa2025-54/"
    }
  ],
  "sourceIdentifier": "security@mozilla.org",
  "vulnStatus": "Modified",
  "weaknesses": [
    {
      "description": [
        {
          "lang": "en",
          "value": "CWE-434"
        }
      ],
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary"
    }
  ]
}



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