CVE-2026-16394
published 2026-07-21CVE-2026-16394: Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
PriorityP353critical9.1CVSS 3.1
AVNACLPRNUINSUCHIHAN
EPSS
0.25%
16.5th percentile
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
Affected
4 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| mozilla | firefox | < Firefox 153 | Firefox 153 |
| mozilla | firefox | < 153.0.0 | 153.0.0 |
| mozilla | thunderbird | < Thunderbird 153 | Thunderbird 153 |
| mozilla | thunderbird | — | — |
CVSS provenance
nvdv3.19.1CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N
vendor_redhat9.1CRITICAL
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Red Hat
firefox: thunderbird: Mitigation bypass in the DOM: Security component
vendor_redhat·2026-07-21·CVSS 9.1
CVE-2026-16394 [CRITICAL] CWE-358 firefox: thunderbird: Mitigation bypass in the DOM: Security component
firefox: thunderbird: Mitigation bypass in the DOM: Security component
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Mitigation bypass in the DOM: Security 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: thunderbird (Red Hat Enterprise Linux 10) - Affected
Package: firefox (Red Hat Enterprise Linux 6) - Not affected
Package: firefox (Red Hat Enterprise Linux 7) - Not affected
Package: firefox (Red Hat Enterprise Linux 8) - Not affected
Package: thunderbird (Red Hat Enterprise
Mozilla
Mozilla Foundation Security Advisory 2026-71: CVE-2026-16394
vendor_mozilla
CVE-2026-16394 Mozilla Foundation Security Advisory 2026-71: CVE-2026-16394
Mozilla Foundation Security Advisory 2026-71
CVE: CVE-2026-16394
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153
Mozilla
Mozilla Foundation Security Advisory 2026-68: CVE-2026-16394
vendor_mozilla·CVSS 9.1
CVE-2026-16394 [CRITICAL] Mozilla Foundation Security Advisory 2026-68: CVE-2026-16394
Mozilla Foundation Security Advisory 2026-68
CVE: CVE-2026-16394
Product: Firefox
Impact: high
Fixed in: Firefox 153
GHSA
Mitigation bypass in the DOM: Security component.
ghsa_unreviewed·2026-07-21
CVE-2026-16394 [CRITICAL] CWE-693 Mitigation bypass in the DOM: Security component.
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 153.
No detection rules found.
No public exploits indexed.
2026-07-21
Published