CVE-2026-110247

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{"bugzilla": {"description": "thunderbird: thunderbird: Arbitrary code execution via integer overflow in libmime", "id": "2550753", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2550753"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.8", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H", "status": "draft"}, "cwe": "CWE-787", "details": ["A flaw was found in Thunderbird. A remote attacker could exploit an integer overflow in the libmime library to achieve arbitrary code execution or cause a Denial of Service (DoS). By sending a sufficiently large email message, an attacker causes buffer size arithmetic to overflow without proper checks. This leads to heap memory corruption as subsequent memory copy operations overwrite adjacent heap allocations with attacker-controlled data."], "name": "CVE-2026-110247", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:8", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 8"}, {"cpe": "cpe:/o:redhat:enterprise_linux:9", "fix_state": "Affected", "package_name": "thunderbird", "product_name": "Red Hat Enterprise Linux 9"}], "public_date": "2026-10-13T18:08:37Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-110247\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-110247\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2071621\nhttps://www.mozilla.org/security/advisories/mfsa2026-109/"], "threat_severity": "Important"}

{"affected": [{"configurations": [{"platform": null, "status": "unaffected", "versions": {"scheme": "generic", "value": "[158,*]"}}], "enrichment": {"confidence": 100.0, "confidence_source": "matching", "scores": [{"score": 100.0, "source": "matching"}]}, "original": {"product": "Thunderbird", "source": "cna", "vendor": "Mozilla"}, "product": "thunderbird", "vendor": "mozilla"}], "created": "2026-10-13T19:45:18.466123+00:00", "updated": "2026-10-28T02:00:16.598662+00:00", "vendors": ["mozilla", "mozilla$PRODUCT$thunderbird"]}