CVE-2026-84639 (GCVE-0-2026-84639)
Vulnerability from cvelistv5
Published
2026-09-01 21:33
Modified
2026-09-02 18:48
Severity ?
9.1 (Critical) - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H
Summary
Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
References
Impacted products
Vendor Product Version
Mozilla Thunderbird Unaffected: 140.15
Unaffected: 153.2
Unaffected: 155
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              "attackComplexity": "LOW",
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              "baseScore": 9.1,
              "baseSeverity": "CRITICAL",
              "confidentialityImpact": "HIGH",
              "integrityImpact": "NONE",
              "privilegesRequired": "NONE",
              "scope": "UNCHANGED",
              "userInteraction": "NONE",
              "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:H",
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          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
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        "title": "CISA ADP Vulnrichment"
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      "affected": [
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          "product": "Thunderbird",
          "vendor": "Mozilla",
          "versions": [
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              "version": "140.15",
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      "credits": [
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          "lang": "en",
          "value": "Ramesh Adhikari, Dr. Faruk Kazi (CoE-CNDS Lab, VJTI, Mumbai, India)"
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          "value": "Triggering an error condition in certain MIME bodies would cause uninitialized memory to be used. This vulnerability was fixed in Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2."
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      "providerMetadata": {
        "dateUpdated": "2026-09-01T21:44:15.369Z",
        "orgId": "f16b083a-5664-49f3-a51e-8d479e5ed7fe",
        "shortName": "mozilla"
      },
      "references": [
        {
          "url": "https://bugzilla.mozilla.org/show_bug.cgi?id=2061087"
        },
        {
          "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/"
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      "title": "Uninitialized memory in MIME parsing"
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    "datePublished": "2026-09-01T21:33:06.251Z",
    "dateReserved": "2026-09-01T21:33:05.937Z",
    "dateUpdated": "2026-09-02T18:48:58.879Z",
    "state": "PUBLISHED"
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  "dataVersion": "5.2"
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