CVE-2026-2804
published 2026-02-24CVE-2026-2804: Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.
PriorityP427medium5.4CVSS 3.1
AVNACLPRNUIRSUCLILAN
EPSS
0.29%
21.0th percentile
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 148.0-1 (sid) | firefox 148.0-1 (sid) |
| mozilla | firefox | < 148.0 | 148.0 |
| mozilla | firefox | — | — |
| mozilla | thunderbird | < 148.0 | 148.0 |
CVSS provenance
nvdv3.15.4MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:L/A:N
osv5.4MEDIUM
vendor_debian5.4MEDIUM
vendor_redhat5.4MEDIUM
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OSV
CVE-2026-2804: Use-after-free in the JavaScript: WebAssembly component
osv·2026-02-24·CVSS 5.4
CVE-2026-2804 [MEDIUM] CVE-2026-2804: Use-after-free in the JavaScript: WebAssembly component
Use-after-free in the JavaScript: WebAssembly component. This vulnerability affects Firefox < 148 and Thunderbird < 148.
GHSA
GHSA-3922-j2hh-9qcf: Use-after-free in the JavaScript: WebAssembly component
ghsa_unreviewed·2026-02-24
CVE-2026-2804 [MEDIUM] CWE-416 GHSA-3922-j2hh-9qcf: Use-after-free in the JavaScript: WebAssembly component
Use-after-free in the JavaScript: WebAssembly component. This vulnerability affects Firefox < 148.
Red Hat
firefox: thunderbird: Use-after-free in the JavaScript: WebAssembly component
vendor_redhat·2026-02-24·CVSS 5.4
CVE-2026-2804 [MEDIUM] 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 affects Firefox < 148 and Thunderbird < 148.
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
Packa
Debian
CVE-2026-2804: firefox - Use-after-free in the JavaScript: WebAssembly component. This vulnerability affe...
vendor_debian·2026·CVSS 5.4
CVE-2026-2804 [MEDIUM] CVE-2026-2804: firefox - Use-after-free in the JavaScript: WebAssembly component. This vulnerability affe...
Use-after-free in the JavaScript: WebAssembly component. This vulnerability affects Firefox < 148 and Thunderbird < 148.
Scope: local
sid: resolved (fixed in 148.0-1)
Mozilla
Mozilla Foundation Security Advisory 2026-13: CVE-2026-2804
vendor_mozilla·CVSS 5.4
CVE-2026-2804 [MEDIUM] Mozilla Foundation Security Advisory 2026-13: CVE-2026-2804
Mozilla Foundation Security Advisory 2026-13
CVE: CVE-2026-2804
Product: Firefox
Impact: high
Fixed in: Firefox 148
Mozilla
Mozilla Foundation Security Advisory 2026-16: CVE-2026-2804
vendor_mozilla·CVSS 5.4
CVE-2026-2804 [MEDIUM] Mozilla Foundation Security Advisory 2026-16: CVE-2026-2804
Mozilla Foundation Security Advisory 2026-16
CVE: CVE-2026-2804
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 148
No detection rules found.
No public exploits indexed.
2026-02-24
Published