CVE-2026-2799
published 2026-02-24CVE-2026-2799: Use-after-free in the DOM: Core & HTML component. This vulnerability was fixed in Firefox 148 and Thunderbird 148.
PriorityP348critical9.8CVSS 3.1
AVNACLPRNUINSUCHIHAH
EPSS
0.32%
24.5th percentile
Use-after-free in the DOM: Core & HTML 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
nvdv3.19.8CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
osv9.8CRITICAL
vendor_debian9.8CRITICAL
vendor_redhat9.8CRITICAL
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Red Hat
firefox: thunderbird: Use-after-free in the DOM: Core & HTML component
vendor_redhat·2026-02-24·CVSS 9.8
CVE-2026-2799 [CRITICAL] firefox: thunderbird: Use-after-free in the DOM: Core & HTML component
firefox: thunderbird: Use-after-free in the DOM: Core & HTML component
Use-after-free in the DOM: Core & HTML 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 DOM: Core & HTML 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
Package: firefox (Red Hat
Debian
CVE-2026-2799: firefox - Use-after-free in the DOM: Core & HTML component. This vulnerability affects Fir...
vendor_debian·2026·CVSS 9.8
CVE-2026-2799 [CRITICAL] CVE-2026-2799: firefox - Use-after-free in the DOM: Core & HTML component. This vulnerability affects Fir...
Use-after-free in the DOM: Core & HTML component. This vulnerability affects Firefox < 148 and Thunderbird < 148.
Scope: local
sid: resolved (fixed in 148.0-1)
Mozilla
Mozilla Foundation Security Advisory 2026-16: CVE-2026-2799
vendor_mozilla·CVSS 9.8
CVE-2026-2799 [CRITICAL] Mozilla Foundation Security Advisory 2026-16: CVE-2026-2799
Mozilla Foundation Security Advisory 2026-16
CVE: CVE-2026-2799
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 148
Mozilla
Mozilla Foundation Security Advisory 2026-13: CVE-2026-2799
vendor_mozilla·CVSS 9.8
CVE-2026-2799 [CRITICAL] Mozilla Foundation Security Advisory 2026-13: CVE-2026-2799
Mozilla Foundation Security Advisory 2026-13
CVE: CVE-2026-2799
Product: Firefox
Impact: high
Fixed in: Firefox 148
GHSA
GHSA-gvhp-5j8m-528x: Use-after-free in the DOM: Core & HTML component
ghsa_unreviewed·2026-02-24
CVE-2026-2799 [CRITICAL] CWE-416 GHSA-gvhp-5j8m-528x: Use-after-free in the DOM: Core & HTML component
Use-after-free in the DOM: Core & HTML component. This vulnerability affects Firefox < 148.
OSV
CVE-2026-2799: Use-after-free in the DOM: Core & HTML component
osv·2026-02-24·CVSS 9.8
CVE-2026-2799 [CRITICAL] CVE-2026-2799: Use-after-free in the DOM: Core & HTML component
Use-after-free in the DOM: Core & HTML component. This vulnerability affects Firefox < 148 and Thunderbird < 148.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=2014551https://www.mozilla.org/security/advisories/mfsa2026-13/https://www.mozilla.org/security/advisories/mfsa2026-16/https://access.redhat.com/security/cve/CVE-2026-2799https://bugzilla.redhat.com/show_bug.cgi?id=2442303https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-2799.json
2026-02-24
Published