CVE-2026-2783: Vulnerability in Mozilla Firefox
Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
AI Analysis
Technical Summary
CVE-2026-2783 is a medium severity vulnerability in Mozilla Firefox involving information disclosure due to just-in-time (JIT) compilation miscompilation within the JavaScript Engine's JIT component. The flaw could allow an attacker to gain access to sensitive information. Mozilla addressed this issue in Firefox 148 and Firefox ESR 140.8. The vulnerability is tracked under CWE-200 (Information Exposure). No public exploitation has been observed. The fix is included in official Mozilla releases.
Potential Impact
The vulnerability results in unauthorized information disclosure, potentially exposing sensitive data to attackers. It does not impact integrity or availability. The CVSS score of 6.5 reflects a moderate risk level. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 148 and Firefox ESR 140.8. Users and administrators should update affected Firefox installations to these or later versions to remediate the issue. Since this is not a cloud service, patching the client software is required. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-2783: Vulnerability in Mozilla Firefox
Description
Information disclosure due to JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 148, Firefox ESR 140.8, Thunderbird 148, and Thunderbird 140.8.
CVSS v3.1
Score 6.5medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-2783 is a medium severity vulnerability in Mozilla Firefox involving information disclosure due to just-in-time (JIT) compilation miscompilation within the JavaScript Engine's JIT component. The flaw could allow an attacker to gain access to sensitive information. Mozilla addressed this issue in Firefox 148 and Firefox ESR 140.8. The vulnerability is tracked under CWE-200 (Information Exposure). No public exploitation has been observed. The fix is included in official Mozilla releases.
Potential Impact
The vulnerability results in unauthorized information disclosure, potentially exposing sensitive data to attackers. It does not impact integrity or availability. The CVSS score of 6.5 reflects a moderate risk level. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 148 and Firefox ESR 140.8. Users and administrators should update affected Firefox installations to these or later versions to remediate the issue. Since this is not a cloud service, patching the client software is required. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-02-19T15:06:17.478Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 699daf70be58cf853bdde204
Added to database: 02/24/2026, 14:02:24 UTC
Last enriched: 04/14/2026, 12:04:12 UTC
Last updated: 07/31/2026, 19:22:58 UTC
Views: 166
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