CVE-2026-92040
published 2026-09-15CVE-2026-92040: Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.
PriorityP345high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.42%
34.9th percentile
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 156 | Firefox 156 |
| mozilla | firefox | < 156.0.0 | 156.0.0 |
| mozilla | thunderbird | < Thunderbird 156 | Thunderbird 156 |
| mozilla | thunderbird | < 156.0 | 156.0 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat6.1MEDIUM
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GHSA
Use-after-free in the JavaScript: WebAssembly component.
ghsa_unreviewed·2026-09-15
CVE-2026-92040 Use-after-free in the JavaScript: WebAssembly component.
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 156.
Red Hat
firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component
vendor_redhat·2026-09-15·CVSS 6.1
CVE-2026-92040 [MEDIUM] CWE-825 firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component
firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 156 and Thunderbird 156.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Use-after-free in the JavaScript: WebAssembly component
Statement: Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Package: firefox (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/firefox-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: rhel10/thunderbird-flatpak (Red Hat Enterprise Linux 10) - Not affected
Package: thunderbird (Red Hat Enterprise Linux 10) - Not affected
Pack
Mozilla
Mozilla Foundation Security Advisory 2026-90: CVE-2026-92040
vendor_mozilla
CVE-2026-92040 Mozilla Foundation Security Advisory 2026-90: CVE-2026-92040
Mozilla Foundation Security Advisory 2026-90
CVE: CVE-2026-92040
Product: Firefox
Impact: low
Fixed in: Firefox 156
Mozilla
Mozilla Foundation Security Advisory 2026-94: CVE-2026-92040
vendor_mozilla
CVE-2026-92040 Mozilla Foundation Security Advisory 2026-94: CVE-2026-92040
Mozilla Foundation Security Advisory 2026-94
CVE: CVE-2026-92040
Product: Thunderbird
Impact: low
Fixed in: Thunderbird 156
No detection rules found.
No public exploits indexed.
2026-09-15
Published