CVE-2026-0884: Vulnerability in Mozilla Firefox
Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
AI Analysis
Technical Summary
CVE-2026-0884 is a use-after-free vulnerability (CWE-416) affecting the JavaScript Engine component in Mozilla Firefox. This type of vulnerability involves accessing memory after it has been freed, which can lead to memory corruption and potentially arbitrary code execution. The vulnerability was addressed and fixed in Firefox 147 and Firefox ESR 140.7. The CVSS v3.1 base score is 9.8, indicating a critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
The vulnerability allows an attacker to exploit a use-after-free condition in the JavaScript Engine, which can result in arbitrary code execution with the privileges of the user running Firefox. This could compromise the confidentiality, integrity, and availability of the affected system. However, there are no known exploits in the wild at the time of this advisory.
Mitigation Recommendations
A fix is available and has been officially released by Mozilla. Users and administrators should update to Firefox 147 or Firefox ESR 140.7 (or later) to remediate this vulnerability. No additional mitigation steps are required beyond applying the official update.
CVE-2026-0884: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript Engine component. This vulnerability was fixed in Firefox 147, Firefox ESR 140.7, Thunderbird 147, and Thunderbird 140.7.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-0884 is a use-after-free vulnerability (CWE-416) affecting the JavaScript Engine component in Mozilla Firefox. This type of vulnerability involves accessing memory after it has been freed, which can lead to memory corruption and potentially arbitrary code execution. The vulnerability was addressed and fixed in Firefox 147 and Firefox ESR 140.7. The CVSS v3.1 base score is 9.8, indicating a critical severity with network attack vector, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality, integrity, and availability.
Potential Impact
The vulnerability allows an attacker to exploit a use-after-free condition in the JavaScript Engine, which can result in arbitrary code execution with the privileges of the user running Firefox. This could compromise the confidentiality, integrity, and availability of the affected system. However, there are no known exploits in the wild at the time of this advisory.
Mitigation Recommendations
A fix is available and has been officially released by Mozilla. Users and administrators should update to Firefox 147 or Firefox ESR 140.7 (or later) to remediate this vulnerability. No additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-01-13T13:30:56.343Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 69664f11a60475309f2ea313
Added to database: 1/13/2026, 1:56:33 PM
Last enriched: 4/14/2026, 11:58:15 AM
Last updated: 5/9/2026, 8:52:28 PM
Views: 313
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.