{"id":"CVE-2025-9181","title":"Uninitialized memory in the JavaScript Engine component","summary":"Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.","severity":"medium","cvss":6.5,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N","cwe":["CWE-457"],"vendor":"mozilla","product":"firefox","affected":["firefox < 128.14.0","firefox < 142.0","firefox >= 140.0, < 140.2.0","thunderbird < 128.14.0","thunderbird < 142.0","thunderbird >= 140.0, < 140.2.0"],"patched":["firefox 140.2.0","thunderbird 140.2.0"],"published":"2025-08-19","updated":"2026-09-30","sourceUpdated":"2026-09-30T18:10:00.190","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2025-9181","references":[{"url":"https://bugzilla.mozilla.org/show_bug.cgi?id=1977130","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-64/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-66/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-67/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-70/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-71/","label":"security@mozilla.org"},{"url":"https://www.mozilla.org/security/advisories/mfsa2025-72/","label":"security@mozilla.org"},{"url":"https://lists.debian.org/debian-lts-announce/2025/08/msg00016.html","label":"af854a3a-2127-422b-91ae-364da2661108"},{"url":"https://lists.debian.org/debian-lts-announce/2025/08/msg00018.html","label":"af854a3a-2127-422b-91ae-364da2661108"}],"tags":["nvd"],"epss":0.00374,"epssPercentile":0.28884,"ingestedAt":"2026-09-30T18:17:24.456Z","slug":"CVE-2025-9181","body":"## Overview\n\nUninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142, Thunderbird 128.14, and Thunderbird 140.2.\n\n## Affected\n\n- `firefox < 128.14.0`\n- `firefox < 142.0`\n- `firefox >= 140.0, < 140.2.0`\n- `thunderbird < 128.14.0`\n- `thunderbird < 142.0`\n- `thunderbird >= 140.0, < 140.2.0`\n\n## Remediation\n\nUpgrade past the affected range:\n\n- `firefox 140.2.0`\n- `thunderbird 140.2.0`","depth":"sunlit","depthScore":36,"depthScoreParts":{"impact":35.8,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[]}