CVE-2026-16387

{
  "id": "CVE-2026-16387",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-21T13:17:13.863",
  "lastModified": "2026-10-24T20:10:00.137",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "Site isolation issue in the Networking component. This vulnerability was fixed in Firefox 153, Firefox ESR 140.13, Thunderbird 153, and Thunderbird 140.13."
    },
    {
      "lang": "es",
      "value": "Problema de aislamiento de sitios en el componente de Redes. Esta vulnerabilidad se corrigió en Firefox 153, Firefox ESR 140.13, Thunderbird 153 y Thunderbird 140.13."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Mozilla",
          "product": "Firefox",
          "versions": [
            {
              "version": "140.13",
              "lessThanOrEqual": "140.*",
              "versionType": "rpm",
              "status": "unaffected"
            },
            {
              "version": "153",
              "lessThanOrEqual": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        },
        {
          "vendor": "Mozilla",
          "product": "Thunderbird",
          "versions": [
            {
              "version": "140.13",
              "lessThanOrEqual": "140.*",
              "versionType": "rpm",
              "status": "unaffected"
            },
            {
              "version": "153",
              "lessThanOrEqual": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
          "baseScore": 9.8,
          "baseSeverity": "CRITICAL",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "HIGH",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 5.9
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-22T17:14:57.789549Z",
          "id": "CVE-2026-16387",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "total"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-200"
        },
        {
          "lang": "en",
          "value": "CWE-284"
        },
        {
          "lang": "en",
          "value": "CWE-346"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
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  "references": [
    {
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2043200",
      "source": "[email protected]",
      "tags": [
        "Permissions Required"
      ]
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-68/",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-70/",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-71/",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    },
    {
      "url": "https://www.mozilla.org/security/advisories/mfsa2026-72/",
      "source": "[email protected]",
      "tags": [
        "Vendor Advisory"
      ]
    }
  ]
}