CVE-2026-84143 (GCVE-0-2026-84143)
Vulnerability from cvelistv5
Published
2026-09-01 12:19
Modified
2026-09-03 17:23
Severity ?
Summary
Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 140.15
Unaffected: 153.2
Unaffected: 155
Create a notification for this product.
   Mozilla Thunderbird Unaffected: 140.15
Unaffected: 153.2
Unaffected: 155
Create a notification for this product.
Show details on NVD website


{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "cvssV3_1": {
              "attackComplexity": "LOW",
              "attackVector": "NETWORK",
              "availabilityImpact": "HIGH",
              "baseScore": 9.8,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "HIGH",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H",
              "version": "3.1"
            }
          },
          {
            "other": {
              "content": {
                "id": "CVE-2026-84143",
                "options": [
                  {
                    "Exploitation": "none"
                  },
                  {
                    "Automatable": "yes"
                  },
                  {
                    "Technical Impact": "total"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-09-03T17:14:23.894743Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "problemTypes": [
          {
            "descriptions": [
              {
                "cweId": "CWE-200",
                "description": "CWE-200 Exposure of Sensitive Information to an Unauthorized Actor",
                "lang": "en",
                "type": "CWE"
              }
            ]
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-09-03T17:23:35.483Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "Firefox",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.15",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.2",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "155",
              "versionType": "rpm"
            }
          ]
        },
        {
          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
            {
              "lessThanOrEqual": "140.*",
              "status": "unaffected",
              "version": "140.15",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "153.*",
              "status": "unaffected",
              "version": "153.2",
              "versionType": "rpm"
            },
            {
              "lessThanOrEqual": "*",
              "status": "unaffected",
              "version": "155",
              "versionType": "rpm"
            }
          ]
        }
      ],
      "credits": [
        {
          "lang": "en",
          "value": "Jan de Mooij, Tom Ritter and the Mozilla Fuzzing Team"
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "supportingMedia": [
            {
              "base64": false,
              "type": "text/html",
              "value": "Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."
            }
          ],
          "value": "Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-09-01T21:44:14.156Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "name": "High Severity internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15",
          "url": "https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048793%2C2054645%2C2057114%2C2059109%2C2061287"
        },
        {
          "name": "Moderate Severity internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15",
          "url": "https://bugzilla.mozilla.org/buglist.cgi?bug_id=2054631%2C2054657%2C2055007%2C2055681%2C2057107%2C2058087%2C2058088%2C2058090%2C2058095%2C2058101%2C2059183%2C2059185%2C2061301%2C2061325"
        },
        {
          "name": "Low Severity internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15",
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2057108"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-82/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-84/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-85/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-86/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-87/"
        },
        {
          "url": "https://www.mozilla.org/security/advisories/mfsa2026-88/"
        }
      ],
      "title": "Internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
    "assignerShortName": "mozilla",
    "cveId": "CVE-2026-84143",
    "datePublished": "2026-09-01T12:19:10.109Z",
    "dateReserved": "2026-09-01T07:26:01.305Z",
    "dateUpdated": "2026-09-03T17:23:35.483Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2",
  "vulnerability-lookup:meta": {
    "vulnrichment": {
      "containers": "{\"adp\": [{\"title\": \"CISA ADP Vulnrichment\", \"metrics\": [{\"cvssV3_1\": {\"scope\": \"UNCHANGED\", \"version\": \"3.1\", \"baseScore\": 9.8, \"attackVector\": \"NETWORK\", \"baseSeverity\": \"CRITICAL\", \"vectorString\": \"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H\", \"integrityImpact\": \"HIGH\", \"userInteraction\": \"NONE\", \"attackComplexity\": \"LOW\", \"availabilityImpact\": \"HIGH\", \"privilegesRequired\": \"NONE\", \"confidentialityImpact\": \"HIGH\"}}, {\"other\": {\"type\": \"ssvc\", \"content\": {\"id\": \"CVE-2026-84143\", \"role\": \"CISA Coordinator\", \"options\": [{\"Exploitation\": \"none\"}, {\"Automatable\": \"yes\"}, {\"Technical Impact\": \"total\"}], \"version\": \"2.0.3\", \"timestamp\": \"2026-09-03T17:14:23.894743Z\"}}}], \"problemTypes\": [{\"descriptions\": [{\"lang\": \"en\", \"type\": \"CWE\", \"cweId\": \"CWE-200\", \"description\": \"CWE-200 Exposure of Sensitive Information to an Unauthorized Actor\"}]}], \"providerMetadata\": {\"orgId\": \"134c704f-9b21-4f2e-91b3-4a467353bcc0\", \"shortName\": \"CISA-ADP\", \"dateUpdated\": \"2026-09-03T17:17:24.835Z\"}}], \"cna\": {\"title\": \"Internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15\", \"credits\": [{\"lang\": \"en\", \"value\": \"Jan de Mooij, Tom Ritter and the Mozilla Fuzzing Team\"}], \"affected\": [{\"vendor\": \"Mozilla\", \"product\": \"Firefox\", \"versions\": [{\"status\": \"unaffected\", \"version\": \"140.15\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"140.*\"}, {\"status\": \"unaffected\", \"version\": \"153.2\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"153.*\"}, {\"status\": \"unaffected\", \"version\": \"155\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"*\"}]}, {\"vendor\": \"Mozilla\", \"product\": \"Thunderbird\", \"versions\": [{\"status\": \"unaffected\", \"version\": \"140.15\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"140.*\"}, {\"status\": \"unaffected\", \"version\": \"153.2\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"153.*\"}, {\"status\": \"unaffected\", \"version\": \"155\", \"versionType\": \"rpm\", \"lessThanOrEqual\": \"*\"}]}], \"references\": [{\"url\": \"https://bugzilla.mozilla.org/buglist.cgi?bug_id=2048793%2C2054645%2C2057114%2C2059109%2C2061287\", \"name\": \"High Severity internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15\"}, {\"url\": \"https://bugzilla.mozilla.org/buglist.cgi?bug_id=2054631%2C2054657%2C2055007%2C2055681%2C2057107%2C2058087%2C2058088%2C2058090%2C2058095%2C2058101%2C2059183%2C2059185%2C2061301%2C2061325\", \"name\": \"Moderate Severity internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15\"}, {\"url\": \"https://bugzilla.mozilla.org/show_bug.cgi?id=2057108\", \"name\": \"Low Severity internally found bugs fixed in Thunderbird 155, Thunderbird ESR 153.2 and Thunderbird ESR 140.15\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-82/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-84/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-85/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-86/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-87/\"}, {\"url\": \"https://www.mozilla.org/security/advisories/mfsa2026-88/\"}], \"descriptions\": [{\"lang\": \"en\", \"value\": \"Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.\", \"supportingMedia\": [{\"type\": \"text/html\", \"value\": \"Internally found bugs present in Thunderbird 154, Thunderbird ESR 153.1 and Thunderbird ESR 140.14. Some of these bugs showed evidence of memory corruption or another security-relevant defect and we presume that with enough effort some of these could have been exploited. This vulnerability was fixed in Firefox 155, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.\", \"base64\": false}]}], \"providerMetadata\": {\"orgId\": \"f16b083a-5664-49f3-a51e-8d479e5ed7fe\", \"shortName\": \"mozilla\", \"dateUpdated\": \"2026-09-01T21:44:14.156Z\"}}}",
      "cveMetadata": "{\"cveId\": \"CVE-2026-84143\", \"state\": \"PUBLISHED\", \"dateUpdated\": \"2026-09-03T17:23:35.483Z\", \"dateReserved\": \"2026-09-01T07:26:01.305Z\", \"assignerOrgId\": \"f16b083a-5664-49f3-a51e-8d479e5ed7fe\", \"datePublished\": \"2026-09-01T12:19:10.109Z\", \"assignerShortName\": \"mozilla\"}",
      "dataType": "CVE_RECORD",
      "dataVersion": "5.2"
    }
  }
}


Log in or create an account to share your comment.




Tags
Taxonomy of the tags.


Loading…

Loading…

Loading…

Sightings

Author Source Type Date

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or seen somewhere by the user.
  • Confirmed: The vulnerability is confirmed from an analyst perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: This vulnerability was exploited and seen by the user reporting the sighting.
  • Patched: This vulnerability was successfully patched by the user reporting the sighting.
  • Not exploited: This vulnerability was not exploited or seen by the user reporting the sighting.
  • Not confirmed: The user expresses doubt about the veracity of the vulnerability.
  • Not patched: This vulnerability was not successfully patched by the user reporting the sighting.


Loading…

Loading…