CVE-2025-9181
published 2025-08-19CVE-2025-9181: Uninitialized memory in the JavaScript Engine component. This vulnerability was fixed in Firefox 142, Firefox ESR 128.14, Firefox ESR 140.2, Thunderbird 142…
PriorityP431medium6.5CVSS 3.1
AVNACLPRNUIRSUCHINAN
EPSS
0.34%
25.8th percentile
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.
Affected
14 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 142.0-1 (sid) | firefox 142.0-1 (sid) |
| debian | firefox-esr | < firefox 142.0-1 (sid) | firefox 142.0-1 (sid) |
| debian | thunderbird | < firefox 142.0-1 (sid) | firefox 142.0-1 (sid) |
| mozilla | firefox | < 128.14.0 | 128.14.0 |
| mozilla | firefox | < 142.0 | 142.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 140.0 < 140.2.0 | 140.2.0 |
| mozilla | thunderbird | < 128.14.0 | 128.14.0 |
| mozilla | thunderbird | < 142.0 | 142.0 |
| mozilla | thunderbird | >= 0 < 1:128.14.0esr-1~deb11u1 | 1:128.14.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:128.14.0esr-1~deb12u1 | 1:128.14.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:128.14.0esr-1~deb13u1 | 1:128.14.0esr-1~deb13u1 |
| mozilla | thunderbird | >= 0 < 1:128.14.0esr-1 | 1:128.14.0esr-1 |
| mozilla | thunderbird | >= 140.0 < 140.2.0 | 140.2.0 |
CVSS provenance
nvdv3.16.5MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
osv6.5MEDIUM
vendor_debian6.5MEDIUM
vendor_redhat6.5MEDIUM
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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2026-02-02
CVE-2025-8031 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, bypass security restrictions, cross-site
tracing, or execute arbitrary code.
Instructions: In general, a standard system update will make all the necessary changes.
Red Hat
thunderbird: firefox: Uninitialized memory in the JavaScript Engine component
vendor_redhat·2025-08-19·CVSS 6.5
CVE-2025-9181 [MEDIUM] CWE-665 thunderbird: firefox: Uninitialized memory in the JavaScript Engine component
thunderbird: firefox: Uninitialized memory in the JavaScript Engine component
Uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 142, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
A flaw was found in Thunderbird and Firefox. The Mozilla Foundation's Security Advisory describes the following issue: Uninitialized memory in the JavaScript Engine component.
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Out of
Debian
CVE-2025-9181: firefox - Uninitialized memory in the JavaScript Engine component. This vulnerability affe...
vendor_debian·2025·CVSS 6.5
CVE-2025-9181 [MEDIUM] CVE-2025-9181: firefox - Uninitialized memory in the JavaScript Engine component. This vulnerability affe...
Uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 142, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
Scope: local
sid: resolved (fixed in 142.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-71: CVE-2025-9181
vendor_mozilla·CVSS 6.5
CVE-2025-9181 [MEDIUM] Mozilla Foundation Security Advisory 2025-71: CVE-2025-9181
Mozilla Foundation Security Advisory 2025-71
CVE: CVE-2025-9181
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 128.14
Mozilla
Mozilla Foundation Security Advisory 2025-67: CVE-2025-9181
vendor_mozilla·CVSS 6.5
CVE-2025-9181 [MEDIUM] Mozilla Foundation Security Advisory 2025-67: CVE-2025-9181
Mozilla Foundation Security Advisory 2025-67
CVE: CVE-2025-9181
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 140.2
Mozilla
Mozilla Foundation Security Advisory 2025-64: CVE-2025-9181
vendor_mozilla·CVSS 6.5
CVE-2025-9181 [MEDIUM] Mozilla Foundation Security Advisory 2025-64: CVE-2025-9181
Mozilla Foundation Security Advisory 2025-64
CVE: CVE-2025-9181
Product: Firefox
Impact: high
Fixed in: Firefox 142
Mozilla
Mozilla Foundation Security Advisory 2025-66: CVE-2025-9181
vendor_mozilla·CVSS 6.5
CVE-2025-9181 [MEDIUM] Mozilla Foundation Security Advisory 2025-66: CVE-2025-9181
Mozilla Foundation Security Advisory 2025-66
CVE: CVE-2025-9181
Product: Firefox ESR
Impact: high
Fixed in: Firefox ESR 128.14
Mozilla
Mozilla Foundation Security Advisory 2025-70: CVE-2025-9181
vendor_mozilla·CVSS 6.5
CVE-2025-9181 [MEDIUM] Mozilla Foundation Security Advisory 2025-70: CVE-2025-9181
Mozilla Foundation Security Advisory 2025-70
CVE: CVE-2025-9181
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 142
Mozilla
Mozilla Foundation Security Advisory 2025-72: CVE-2025-9181
vendor_mozilla·CVSS 6.5
CVE-2025-9181 [MEDIUM] Mozilla Foundation Security Advisory 2025-72: CVE-2025-9181
Mozilla Foundation Security Advisory 2025-72
CVE: CVE-2025-9181
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140.2
OSV
CVE-2025-9181: Uninitialized memory in the JavaScript Engine component
osv·2025-08-19·CVSS 6.5
CVE-2025-9181 [MEDIUM] CVE-2025-9181: Uninitialized memory in the JavaScript Engine component
Uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 142, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
GHSA
GHSA-4c9v-rqpw-wrj7: Uninitialized memory in the JavaScript Engine component
ghsa_unreviewed·2025-08-19
CVE-2025-9181 [MEDIUM] CWE-457 GHSA-4c9v-rqpw-wrj7: Uninitialized memory in the JavaScript Engine component
Uninitialized memory in the JavaScript Engine component. This vulnerability affects Firefox < 142, Firefox ESR < 128.14, Firefox ESR < 140.2, Thunderbird < 142, Thunderbird < 128.14, and Thunderbird < 140.2.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=1977130https://www.mozilla.org/security/advisories/mfsa2025-64/https://www.mozilla.org/security/advisories/mfsa2025-66/https://www.mozilla.org/security/advisories/mfsa2025-67/https://www.mozilla.org/security/advisories/mfsa2025-70/https://www.mozilla.org/security/advisories/mfsa2025-71/https://www.mozilla.org/security/advisories/mfsa2025-72/https://lists.debian.org/debian-lts-announce/2025/08/msg00016.htmlhttps://lists.debian.org/debian-lts-announce/2025/08/msg00018.html
2025-08-19
Published