{"id":"CVE-2026-110247","state":"PUBLISHED","title":"Integer overflow in libmime buffer growth could lead to heap corruption","description":"Several buffer-growth sites in libmime performed size arithmetic in 32-bit types without overflow checks. On a sufficiently large message the growth guard could fail open, or the buffer could be reallocated smaller than required, and a subsequent memcpy would then write attacker-controlled data across adjacent heap allocations. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.6.","publishedAt":"2026-10-13T18:08:37.608Z","updatedAt":"2026-10-27T18:27:45.455Z","severity":{"score":8.4,"label":"High","version":"3.1","vector":"CVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","source":"CISA-ADP"},"assigner":"mozilla","products":["Mozilla Thunderbird"],"affected":[{"vendor":"Mozilla","product":"Thunderbird","versions":[{"version":"153.6","status":"unaffected","lessThanOrEqual":"153.*","versionType":"rpm"},{"version":"158","status":"unaffected","lessThanOrEqual":"*","versionType":"rpm"}]}],"references":["https://bugzilla.mozilla.org/show_bug.cgi?id=2071621","https://www.mozilla.org/security/advisories/mfsa2026-109/","https://www.mozilla.org/security/advisories/mfsa2026-122/"],"weaknesses":["CWE-190"],"ingestedAt":"2026-10-29T20:10:33.477Z","source":{"repository":"CVEProject/cvelistV5","path":"cves/2026/110xxx/CVE-2026-110247.json","commit":"556c9d3a8cd17e218bb8e452ba7cd619a384ff47"},"raw":{"dataType":"CVE_RECORD","dataVersion":"5.2","cveMetadata":{"cveId":"CVE-2026-110247","state":"PUBLISHED","datePublished":"2026-10-13T18:08:37.608Z","dateUpdated":"2026-10-27T18:27:45.455Z","assignerShortName":"mozilla","assignerOrgId":"f16b083a-5664-49f3-a51e-8d479e5ed7fe","dateReserved":"2026-10-13T18:08:37.322Z"},"containers":{"cna":{"title":"Integer overflow in libmime buffer growth could lead to heap corruption","descriptions":[{"lang":"en","value":"Several buffer-growth sites in libmime performed size arithmetic in 32-bit types without overflow checks. On a sufficiently large message the growth guard could fail open, or the buffer could be reallocated smaller than required, and a subsequent memcpy would then write attacker-controlled data across adjacent heap allocations. This vulnerability was fixed in Thunderbird 158 and Thunderbird 153.6."}],"affected":[{"vendor":"Mozilla","product":"Thunderbird","versions":[{"version":"153.6","status":"unaffected","lessThanOrEqual":"153.*","versionType":"rpm"},{"version":"158","status":"unaffected","lessThanOrEqual":"*","versionType":"rpm"}]}],"references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=2071621"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-109/"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-122/"}],"providerMetadata":{"shortName":"mozilla","orgId":"f16b083a-5664-49f3-a51e-8d479e5ed7fe","dateUpdated":"2026-10-27T18:27:45.455Z"},"credits":[{"lang":"en","value":"Ahmed Albalawi"}]},"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"cvssV3_1":{"scope":"UNCHANGED","version":"3.1","baseScore":8.4,"attackVector":"LOCAL","baseSeverity":"HIGH","vectorString":"CVSS:3.1/AV:L/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":{"timestamp":"2026-10-20T17:08:54.337976Z","id":"CVE-2026-110247","options":[{"Exploitation":"none"},{"Automatable":"no"},{"Technical Impact":"total"}],"role":"CISA Coordinator","version":"2.0.3"}}}],"problemTypes":[{"descriptions":[{"cweId":"CWE-190","type":"CWE","lang":"en","description":"CWE-190 Integer Overflow or Wraparound"}]}],"providerMetadata":{"shortName":"CISA-ADP","orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","dateUpdated":"2026-10-20T17:09:29.220Z"}}]}}}