CVE-2026-74982: Vulnerability in Mozilla Firefox
CVE-2026-74982 is a denial-of-service vulnerability in the Widget component of Mozilla Firefox. This issue was resolved in Firefox version 154 and Firefox ESR 153.1, as well as Thunderbird 154 and Thunderbird 153.1. The vulnerability allows an attacker to cause a denial of service, impacting availability but not confidentiality or integrity.
AI Analysis
Technical Summary
This vulnerability (CVE-2026-74982) affects the Widget component in Mozilla Firefox and can be exploited to cause a denial-of-service condition. It has a CVSS 3.1 base score of 7.5, indicating high severity, with an attack vector over the network, low attack complexity, no privileges required, and no user interaction needed. The vulnerability was fixed in Firefox 154 and Firefox ESR 153.1. The vendor advisory confirms the fix and provides no indication of active exploitation in the wild.
Potential Impact
Successful exploitation of this vulnerability results in denial of service, which can disrupt the availability of the Firefox browser. There is no impact on confidentiality or integrity according to the CVSS vector and description.
Mitigation Recommendations
Users should update to Firefox 154, Firefox ESR 153.1, Thunderbird 154, or Thunderbird 153.1 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in these versions. No additional mitigation is required once updated.
CVE-2026-74982: Vulnerability in Mozilla Firefox
Description
CVE-2026-74982 is a denial-of-service vulnerability in the Widget component of Mozilla Firefox. This issue was resolved in Firefox version 154 and Firefox ESR 153.1, as well as Thunderbird 154 and Thunderbird 153.1. The vulnerability allows an attacker to cause a denial of service, impacting availability but not confidentiality or integrity.
CVSS v3.1
Score 7.5high
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
Run on your own infrastructure? Check whether these packages are installed with threat-finder — our free open-source scanner.
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability (CVE-2026-74982) affects the Widget component in Mozilla Firefox and can be exploited to cause a denial-of-service condition. It has a CVSS 3.1 base score of 7.5, indicating high severity, with an attack vector over the network, low attack complexity, no privileges required, and no user interaction needed. The vulnerability was fixed in Firefox 154 and Firefox ESR 153.1. The vendor advisory confirms the fix and provides no indication of active exploitation in the wild.
Potential Impact
Successful exploitation of this vulnerability results in denial of service, which can disrupt the availability of the Firefox browser. There is no impact on confidentiality or integrity according to the CVSS vector and description.
Mitigation Recommendations
Users should update to Firefox 154, Firefox ESR 153.1, Thunderbird 154, or Thunderbird 153.1 or later to remediate this vulnerability. The vendor advisory confirms that the issue is fixed in these versions. No additional mitigation is required once updated.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:59:10.459Z
- State
- PUBLISHED
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-74/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-77/","vendor":"Mozilla"}]
Threat ID: 6a84550bc6e8be03323676be
Added to database: 08/18/2026, 12:50:19 UTC
Last enriched: 09/11/2026, 21:48:19 UTC
Last updated: 10/02/2026, 16:37:10 UTC
Views: 49
Community Reviews
0 reviewsCrowdsource mitigation strategies, share intel context, and vote on the most helpful responses. Sign in to add your voice and help keep defenders ahead.
Want to contribute mitigation steps or threat intel context? Sign in or create an account to join the community discussion.
Actions
Updates to AI analysis require Pro Console access. Upgrade inside Console → Billing.
Need more coverage?
Upgrade to Pro Console for AI refresh and higher limits.
For incident response and remediation, OffSeq services can help resolve threats faster.
Latest Threats
Check if your credentials are on the dark web
Instant breach scanning across billions of leaked records. Free tier available.