CVE-2026-16366
published 2026-07-21CVE-2026-16366: Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
PriorityP349high8.8CVSS 3.1
AVNACLPRNUIRSUCHIHAH
EPSS
0.27%
18.8th percentile
Privilege escalation in the DOM: Navigation 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 | < 153.0 | 153.0 |
CVSS provenance
nvdv3.18.8HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
vendor_redhat8.8HIGH
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
Red Hat
firefox: thunderbird: Privilege escalation in the DOM: Navigation component
vendor_redhat·2026-07-21·CVSS 8.8
CVE-2026-16366 [HIGH] CWE-270 firefox: thunderbird: Privilege escalation in the DOM: Navigation component
firefox: thunderbird: Privilege escalation in the DOM: Navigation component
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue:
Privilege escalation in the DOM: Navigation 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) - Not 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 H
Mozilla
Mozilla Foundation Security Advisory 2026-68: CVE-2026-16366
vendor_mozilla
CVE-2026-16366 Mozilla Foundation Security Advisory 2026-68: CVE-2026-16366
Mozilla Foundation Security Advisory 2026-68
CVE: CVE-2026-16366
Product: Firefox
Impact: high
Fixed in: Firefox 153
Mozilla
Mozilla Foundation Security Advisory 2026-71: CVE-2026-16366
vendor_mozilla
CVE-2026-16366 Mozilla Foundation Security Advisory 2026-71: CVE-2026-16366
Mozilla Foundation Security Advisory 2026-71
CVE: CVE-2026-16366
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 153
GHSA
Privilege escalation in the DOM: Navigation component.
ghsa_unreviewed·2026-07-21
CVE-2026-16366 [CRITICAL] CWE-269 Privilege escalation in the DOM: Navigation component.
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 153.
No detection rules found.
No public exploits indexed.
2026-07-21
Published