CVE-2026-14899

{
  "id": "CVE-2026-14899",
  "sourceIdentifier": "[email protected]",
  "published": "2026-07-22T20:16:48.383",
  "lastModified": "2026-10-24T13:10:00.147",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "The code to parse MIME headers for display when forwarding a message (if the setting to view all headers was enabled) had an off-by-one error, allowing a single byte to be read from the memory after the buffer for the headers, and potentially crashing Thunderbird. This vulnerability was fixed in Thunderbird 153 and Thunderbird 140.13."
    },
    {
      "lang": "es",
      "value": "El código para analizar encabezados MIME para mostrar al reenviar un mensaje (si la configuración para ver todos los encabezados estaba habilitada) tenía un error de off-by-one, permitiendo que se leyera un solo byte de la memoria después del búfer para los encabezados, y potencialmente bloqueando Thunderbird. Esta vulnerabilidad se corrigió en Thunderbird 153 y Thunderbird 140.13."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "Mozilla",
          "product": "Thunderbird",
          "versions": [
            {
              "version": "140.13",
              "lessThanOrEqual": "140.*",
              "versionType": "rpm",
              "status": "unaffected"
            },
            {
              "version": "153",
              "lessThanOrEqual": "*",
              "versionType": "rpm",
              "status": "unaffected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
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        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N",
          "baseScore": 7.5,
          "baseSeverity": "HIGH",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "NONE",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "HIGH",
          "integrityImpact": "NONE",
          "availabilityImpact": "NONE"
        },
        "exploitabilityScore": 3.9,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
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        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-07-27T17:12:35.358996Z",
          "id": "CVE-2026-14899",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "yes"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-193"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
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              "vulnerable": true,
              "criteria": "cpe:2.3:a:mozilla:thunderbird:*:*:*:*:esr:*:*:*",
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  "references": [
    {
      "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2046137",
      "source": "[email protected]",
      "tags": [
        "Permissions Required"
      ]
    },
    {
      "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"
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}