CVE-2026-84641

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{"bugzilla": {"description": "thunderbird: Thunderbird: Information disclosure via malicious IMAP server response", "id": "2527115", "url": "https://bugzilla.redhat.com/show_bug.cgi?id=2527115"}, "csaw": false, "cvss3": {"cvss3_base_score": "8.3", "cvss3_scoring_vector": "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:L/A:H", "status": "draft"}, "cwe": "CWE-825", "details": ["A flaw was found in Thunderbird. A remote attacker, by operating a malicious Internet Message Access Protocol (IMAP) server, could send a specially crafted ID response. This could trigger a use-after-free vulnerability and lead to heap-memory disclosure, allowing sensitive heap contents to be persisted to the prefs.js file."], "name": "CVE-2026-84641", "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": "2026-09-01T21:33:07Z", "references": ["https://www.cve.org/CVERecord?id=CVE-2026-84641\nhttps://nvd.nist.gov/vuln/detail/CVE-2026-84641\nhttps://bugzilla.mozilla.org/show_bug.cgi?id=2057805\nhttps://www.mozilla.org/security/advisories/mfsa2026-86/"], "threat_severity": "Important"}

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