CVE-2026-92021
published 2026-09-15CVE-2026-92021: Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16.
PriorityP346high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.28%
19.2th percentile
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16 and Thunderbird 140.16.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < 140.16.0 | 140.16.0 |
| mozilla | firefox_esr | < Firefox ESR 140.16 | Firefox ESR 140.16 |
| mozilla | thunderbird | < Thunderbird 140.16 | Thunderbird 140.16 |
| mozilla | thunderbird | < 140.16.0 | 140.16.0 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat7.5HIGH
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VulDB
Mozilla Firefox up to 140.15 JIT use after free (WID-SEC-2026-3375)
vuldb·2026-09-22·CVSS 8.8
CVE-2026-92021 [HIGH] Mozilla Firefox up to 140.15 JIT use after free (WID-SEC-2026-3375)
A vulnerability labeled as critical has been found in Mozilla Firefox up to 140.15. This vulnerability affects unknown code of the component JIT. Executing a manipulation can lead to use after free.
This vulnerability is handled as CVE-2026-92021. The attack can be executed remotely. There is not any exploit available.
The affected component should be upgraded.
GHSA
Use-after-free in the JavaScript Engine: JIT component.
ghsa_unreviewed·2026-09-15
CVE-2026-92021 Use-after-free in the JavaScript Engine: JIT component.
Use-after-free in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox ESR 140.16.
Red Hat
firefox: Use-after-free in the JavaScript Engine: JIT component
vendor_redhat·2026-09-15·CVSS 7.5
CVE-2026-92021 [HIGH] CWE-825 firefox: Use-after-free in the JavaScript Engine: JIT component
firefox: Use-after-free in the JavaScript Engine: JIT component
A flaw was found in Firefox. The Mozilla Foundation's Security Advisory describes the following issue:
Use-after-free in the JavaScript Engine: JIT component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Mozilla
Mozilla Foundation Security Advisory 2026-95: CVE-2026-92021
vendor_mozilla
CVE-2026-92021 Mozilla Foundation Security Advisory 2026-95: CVE-2026-92021
Mozilla Foundation Security Advisory 2026-95
CVE: CVE-2026-92021
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 140.16
Mozilla
Mozilla Foundation Security Advisory 2026-92: CVE-2026-92021
vendor_mozilla
CVE-2026-92021 Mozilla Foundation Security Advisory 2026-92: CVE-2026-92021
Mozilla Foundation Security Advisory 2026-92
CVE: CVE-2026-92021
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 140.16
No detection rules found.
No public exploits indexed.
2026-09-15
Published