CVE-2026-8390: Vulnerability in Mozilla Firefox
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150.0.3.
AI Analysis
Technical Summary
This vulnerability involves a use-after-free condition in the WebAssembly component of Mozilla Firefox's JavaScript engine. Use-after-free bugs occur when a program continues to use memory after it has been freed, potentially leading to arbitrary code execution or crashes. Mozilla fixed this issue in Firefox 150.0.3 as part of a security update addressing multiple high-impact vulnerabilities in the JavaScript engine.
Potential Impact
The vulnerability is rated as high impact by Mozilla, indicating it could allow an attacker to cause significant harm such as arbitrary code execution or browser compromise. However, there are no reports of active exploitation in the wild at the time of disclosure.
Mitigation Recommendations
Mozilla has released Firefox version 150.0.3 which includes the fix for CVE-2026-8390. Users should update to this version or later to remediate the vulnerability. No additional mitigation steps are required beyond applying the official update.
CVE-2026-8390: Vulnerability in Mozilla Firefox
Description
Use-after-free in the JavaScript: WebAssembly component. This vulnerability was fixed in Firefox 150.0.3.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves a use-after-free condition in the WebAssembly component of Mozilla Firefox's JavaScript engine. Use-after-free bugs occur when a program continues to use memory after it has been freed, potentially leading to arbitrary code execution or crashes. Mozilla fixed this issue in Firefox 150.0.3 as part of a security update addressing multiple high-impact vulnerabilities in the JavaScript engine.
Potential Impact
The vulnerability is rated as high impact by Mozilla, indicating it could allow an attacker to cause significant harm such as arbitrary code execution or browser compromise. However, there are no reports of active exploitation in the wild at the time of disclosure.
Mitigation Recommendations
Mozilla has released Firefox version 150.0.3 which includes the fix for CVE-2026-8390. Users should update to this version or later to remediate the vulnerability. No additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-12T12:36:13.277Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-45/","vendor":"Mozilla"}]
Threat ID: 6a032959cbff5d8610e85ad2
Added to database: 5/12/2026, 1:21:29 PM
Last enriched: 5/12/2026, 1:37:25 PM
Last updated: 5/13/2026, 2:50:54 AM
Views: 13
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