CVE-2026-8962
HighCVSS 8.1Exploitation Probability (EPSS)
Low risk30th percentile - higher than 30% of all known CVEs
Summary
A vulnerability in the DOM: Security component of Firefox and Thunderbird. The issue was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
Risk Assessment
An attacker may bypass DOM security mechanisms, potentially leading to violation of Content Security Policy (CSP) or other protective measures.
Recommendation
Update Firefox to version 151 or later, Firefox ESR to 140.11 or later, Thunderbird to 151 or later, or Thunderbird ESR to 140.11 or later.
Other vulnerabilities in Firefox
See all- CVE-2026-84141Critical
Integer overflow in the Graphics: ImageLib component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
- CVE-2026-84140Critical
Site isolation issue in the DOM: Navigation component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
- CVE-2026-84134Critical
Other issue in the Profile Backup component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
- CVE-2026-84133Critical
Site isolation issue in the DOM: Push Subscriptions component. This vulnerability was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
- CVE-2026-84129Critical
The vulnerability concerns a site isolation issue in the DOM: Navigation component in Firefox and Thunderbird. The flaw was fixed in Firefox 155, Firefox ESR 153.2, Thunderbird 155, and Thunderbird 153.2.
- CVE-2026-84121Critical
Sandbox escape due to use-after-free in the DOM: Security component. This vulnerability was fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
- CVE-2026-84119Critical
Sandbox escape vulnerability due to use-after-free in the DOM: Navigation component. Fixed in Firefox 155, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 155, Thunderbird 140.15, and Thunderbird 153.2.
- CVE-2026-75874Critical
Sandbox escape in the Remote Settings Client component. Fixed in Firefox 154, Thunderbird 154, Firefox ESR 115.40, Firefox ESR 140.15, Firefox ESR 153.2, Thunderbird 140.15, and Thunderbird 153.2.
- CVE-2026-74986Critical
Site isolation issue in the CSS Parsing and Computation component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
- CVE-2026-74985Critical
Privilege escalation in the Enterprise Policies component. This vulnerability was fixed in Firefox 154, Firefox ESR 153.1, Thunderbird 154, and Thunderbird 153.1.
Original NVD description (English source)
Mitigation bypass in the DOM: Security component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.