CVE-2026-4727: Vulnerability in Mozilla Firefox
Denial-of-service in the Libraries component in NSS. This vulnerability was fixed in Firefox 149 and Thunderbird 149.
AI Analysis
Technical Summary
This vulnerability, identified as CVE-2026-4727, involves a denial-of-service condition in the NSS Libraries component within Mozilla Firefox. The flaw could allow an attacker to cause the application to become unavailable or crash. It is classified under CWE-400 (Uncontrolled Resource Consumption). The issue was resolved in Firefox 149, as documented in Mozilla's security advisory MFSA 2026-20. The CVSS v3.1 base score is 7.5, with attack vector network, low attack complexity, no privileges required, no user interaction, and impact limited to availability.
Potential Impact
Successful exploitation of this vulnerability could result in denial-of-service, causing Firefox to crash or become unresponsive, impacting availability. There is no impact on confidentiality or integrity. No known exploits have been reported in the wild, reducing immediate risk. The vulnerability affects Firefox versions prior to 149.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 149. Users and administrators should update affected Firefox installations to version 149 or later to remediate this issue. No additional mitigation actions are required beyond applying the official update.
CVE-2026-4727: Vulnerability in Mozilla Firefox
Description
Denial-of-service in the Libraries component in NSS. This vulnerability was fixed in Firefox 149 and Thunderbird 149.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability, identified as CVE-2026-4727, involves a denial-of-service condition in the NSS Libraries component within Mozilla Firefox. The flaw could allow an attacker to cause the application to become unavailable or crash. It is classified under CWE-400 (Uncontrolled Resource Consumption). The issue was resolved in Firefox 149, as documented in Mozilla's security advisory MFSA 2026-20. The CVSS v3.1 base score is 7.5, with attack vector network, low attack complexity, no privileges required, no user interaction, and impact limited to availability.
Potential Impact
Successful exploitation of this vulnerability could result in denial-of-service, causing Firefox to crash or become unresponsive, impacting availability. There is no impact on confidentiality or integrity. No known exploits have been reported in the wild, reducing immediate risk. The vulnerability affects Firefox versions prior to 149.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 149. Users and administrators should update affected Firefox installations to version 149 or later to remediate this issue. No additional mitigation actions are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-03-23T23:22:53.470Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 69c2878af4197a8e3b32076d
Added to database: 3/24/2026, 12:46:02 PM
Last enriched: 4/14/2026, 12:14:29 PM
Last updated: 5/7/2026, 5:03:39 AM
Views: 169
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