CVE-2026-109729
published 2026-10-13CVE-2026-109729: Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158…
PriorityP428medium5.4CVSS 3.1
AVNACLPRNUIRSUCLILAN
EPSS
0.24%
14.3th percentile
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, Firefox ESR 153.5, Thunderbird 158, and Thunderbird 153.5.
Affected
6 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 158 | Firefox 158 |
| mozilla | firefox | — | — |
| mozilla | firefox_esr | < Firefox ESR 153.5 | Firefox ESR 153.5 |
| mozilla | firefox_esr | < Firefox ESR 115.43 | Firefox ESR 115.43 |
| mozilla | thunderbird | < Thunderbird 153.5 | Thunderbird 153.5 |
| mozilla | thunderbird | < Thunderbird 158 | Thunderbird 158 |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
vendor_redhat5.4MEDIUM
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GHSA
Use-after-free in the JavaScript Engine: JIT component.
ghsa_unreviewed·2026-10-13
CVE-2026-109729 [MEDIUM] CWE-416 Use-after-free in the JavaScript Engine: JIT component.
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 158, Firefox ESR 115.43, and Firefox ESR 153.5.
Red Hat
firefox: firefox: arbitrary code execution via use-after-free in JIT compiler
vendor_redhat·2026-10-13·CVSS 5.4
CVE-2026-109729 [MEDIUM] CWE-825 firefox: firefox: arbitrary code execution via use-after-free in JIT compiler
firefox: firefox: arbitrary code execution via use-after-free in JIT compiler
A flaw was found in firefox. A use-after-free memory vulnerability in the JavaScript Just-In-Time (JIT) engine allows a remote attacker to achieve arbitrary code execution or cause a Denial of Service (DoS). By tricking a user into visiting a malicious webpage, an attacker can exploit incorrect memory handling to compromise the browser process.
Package: firefox (Red Hat Enterprise Linux 10) - Will not fix
Package: firefox (Red Hat Enterprise Linux 7) - Will not fix
Package: firefox (Red Hat Enterprise Linux 8) - Will not fix
Package: firefox (Red Hat Enterprise Linux 9) - Will not fix
Mozilla
Mozilla Foundation Security Advisory 2026-108: CVE-2026-109729
vendor_mozilla·CVSS 5.4
CVE-2026-109729 [MEDIUM] Mozilla Foundation Security Advisory 2026-108: CVE-2026-109729
Mozilla Foundation Security Advisory 2026-108
CVE: CVE-2026-109729
Product: Firefox ESR
Impact: low
Fixed in: Firefox ESR 153.5
Mozilla
Mozilla Foundation Security Advisory 2026-110: CVE-2026-109729
vendor_mozilla·CVSS 5.4
CVE-2026-109729 [MEDIUM] Mozilla Foundation Security Advisory 2026-110: CVE-2026-109729
Mozilla Foundation Security Advisory 2026-110
CVE: CVE-2026-109729
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 153.5
Mozilla
Mozilla Foundation Security Advisory 2026-106: CVE-2026-109729
vendor_mozilla·CVSS 5.4
CVE-2026-109729 [MEDIUM] Mozilla Foundation Security Advisory 2026-106: CVE-2026-109729
Mozilla Foundation Security Advisory 2026-106
CVE: CVE-2026-109729
Product: Firefox
Impact: low
Fixed in: Firefox 158
Mozilla
Mozilla Foundation Security Advisory 2026-109: CVE-2026-109729
vendor_mozilla·CVSS 5.4
CVE-2026-109729 [MEDIUM] Mozilla Foundation Security Advisory 2026-109: CVE-2026-109729
Mozilla Foundation Security Advisory 2026-109
CVE: CVE-2026-109729
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 158
Mozilla
Mozilla Foundation Security Advisory 2026-107: CVE-2026-109729
vendor_mozilla·CVSS 5.4
CVE-2026-109729 [MEDIUM] Mozilla Foundation Security Advisory 2026-107: CVE-2026-109729
Mozilla Foundation Security Advisory 2026-107
CVE: CVE-2026-109729
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 115.43
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2074632https://www.mozilla.org/security/advisories/mfsa2026-106/https://www.mozilla.org/security/advisories/mfsa2026-107/https://www.mozilla.org/security/advisories/mfsa2026-108/https://www.mozilla.org/security/advisories/mfsa2026-109/https://www.mozilla.org/security/advisories/mfsa2026-110/
2026-10-13
Published