CVE-2026-74939: Vulnerability in Mozilla Firefox
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, and Firefox ESR 153.1.
AI Analysis
Technical Summary
CVE-2026-74939 is a privilege escalation vulnerability affecting the DOM Navigation component in Mozilla Firefox. It was reported by choeseyeong and classified as high impact. The vulnerability was fixed in Firefox 154 and Firefox ESR 115.39, 140.14, and 153.1. The Mozilla advisories confirm the fix and classify the issue as high severity. No CVSS score is provided. No evidence of active exploitation has been reported. The vulnerability is part of a set of multiple security issues fixed in these releases.
Potential Impact
The vulnerability allows an attacker to escalate privileges within the Firefox browser, potentially enabling unauthorized actions or access to restricted browser functions. Given the high impact rating by Mozilla, successful exploitation could compromise browser security and user data integrity. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154 and Firefox ESR versions 115.39, 140.14, and 153.1. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-74939: Vulnerability in Mozilla Firefox
Description
Privilege escalation in the DOM: Navigation component. This vulnerability was fixed in Firefox 154, Firefox ESR 115.39, Firefox ESR 140.14, and Firefox ESR 153.1.
CVSS v3.1
Score 8.8high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-74939 is a privilege escalation vulnerability affecting the DOM Navigation component in Mozilla Firefox. It was reported by choeseyeong and classified as high impact. The vulnerability was fixed in Firefox 154 and Firefox ESR 115.39, 140.14, and 153.1. The Mozilla advisories confirm the fix and classify the issue as high severity. No CVSS score is provided. No evidence of active exploitation has been reported. The vulnerability is part of a set of multiple security issues fixed in these releases.
Potential Impact
The vulnerability allows an attacker to escalate privileges within the Firefox browser, potentially enabling unauthorized actions or access to restricted browser functions. Given the high impact rating by Mozilla, successful exploitation could compromise browser security and user data integrity. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 154 and Firefox ESR versions 115.39, 140.14, and 153.1. Users and administrators should update to these versions or later to remediate the issue. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:57:35.911Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-75/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-76/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-77/","vendor":"Mozilla"}]
Threat ID: 6a845502c6e8be03323673a1
Added to database: 08/18/2026, 12:50:10 UTC
Last enriched: 08/18/2026, 14:21:42 UTC
Last updated: 08/18/2026, 18:35:09 UTC
Views: 3
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