Privilege escalation in the DOM: Navigation component
Published Jul 21, 2026
8.8
HIGHCVSS 3.1
EPSS 0.27%
Description
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 153 and Thunderbird 153.
Affected products
No data.
- < 153.0.0
- < 153.0
No data.
Red Hat Enterprise Linux 10
firefox
Not affected
Red Hat Enterprise Linux 10
rhel10/firefox-flatpak
Not affected
Red Hat Enterprise Linux 10
thunderbird
Not affected
Red Hat Enterprise Linux 6
firefox
Not affected
Red Hat Enterprise Linux 7
firefox
Not affected
Red Hat Enterprise Linux 8
firefox
Not affected
Red Hat Enterprise Linux 8
thunderbird
Not affected
Red Hat Enterprise Linux 9
firefox
Not affected
Red Hat Enterprise Linux 9
thunderbird
Not affected
| Product | Package | State | Advisory |
|---|---|---|---|
| Red Hat Enterprise Linux 10 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 10 | rhel10/firefox-flatpak | Not affected | n/a |
| Red Hat Enterprise Linux 10 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 6 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 7 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 8 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 8 | thunderbird | Not affected | n/a |
| Red Hat Enterprise Linux 9 | firefox | Not affected | n/a |
| Red Hat Enterprise Linux 9 | thunderbird | Not affected | n/a |
No package ranges for this CVE.
Remediation
Red Hat statement
Red Hat Product Security rates the severity of this flaw as determined by the Mozilla Foundation Security Advisory.
Metrics
No CVSS v4.0 score for this CVE.
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
1 other source (Red Hat) ▾
CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:H
No CVSS v3.0 score for this CVE.
No CVSS v2.0 score for this CVE.
This CVE is not in the KEV list.
CISA SSVC (Vulnrichment)
Stakeholder-Specific Vulnerability Categorization from CISA ADP.
Exploitation
NoneAutomatable
NoTechnical Impact
TotalDecision
n/aAssessed Jul 24, 2026 · SSVC 2.0.3
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
Jul–Oct 2026- EPSS v5
Percentile over time
- EPSS v5
Table of values (2 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 0.27% (0.00269) | 17.22th | v5 (v2026.06.15) |
| Jul 22, 2026 | 0.14% (0.00141) | 3.85th | v5 (v2026.06.15) |
References (9)
- https://access.redhat.com/security/cve/CVE-2026-16366 Vendor Advisory
- https://bugzilla.mozilla.org/show_bug.cgi?id=2049181 Permissions Required
- https://bugzilla.redhat.com/show_bug.cgi?id=2503458 Issue Tracking
- https://nvd.nist.gov/vuln/detail/CVE-2026-16366
- https://www.cve.org/CVERecord?id=CVE-2026-16366
- https://www.mozilla.org/security/advisories/mfsa2026-68/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-68/#CVE-2026-16366
- https://www.mozilla.org/security/advisories/mfsa2026-71/ Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2026-71/#CVE-2026-16366
Change history (0)
No recorded changes yet.