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EPSS 0.3%top 74%

CVE-2026-8389: Vulnerability in Mozilla Firefox

0
High
VulnerabilityCVE-2026-8389cvecve-2026-8389
Published: 05/12/2026 (05/12/2026, 12:36:12 UTC)
Source: CVE Database V5
Vendor/Project: Mozilla
Product: Firefox

Description

JIT miscompilation in the JavaScript Engine: JIT component. This vulnerability was fixed in Firefox 150.0.3.

CVSS v3.1

Score 8.8high

Attack Vector
Network
Attack Complexity
Low
Privileges Required
None
User Interaction
Required
Scope
Unchanged
Confidentiality
High
Integrity
High
Availability
High
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H

Affected software

GitHub Actionsmore threats →ai
mozilla/firefox
pkg:github/mozilla/firefox
Affected versions
<150.0.3

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AI-Powered Analysis

Machine-generated threat intelligence

AILast updated: 07/15/2026, 08:14:13 UTC

Technical Analysis

CVE-2026-8389 describes a vulnerability in the JIT component of the JavaScript Engine in Mozilla Firefox. The flaw involves miscompilation during JIT processing, potentially causing incorrect execution of JavaScript code. This vulnerability was addressed and fixed in Firefox version 150.0.3. The CVSS v3.1 base score is 8.8, indicating high severity with network attack vector, low attack complexity, no privileges required, user interaction required, unchanged scope, and high impact on confidentiality, integrity, and availability.

Potential Impact

Successful exploitation of this vulnerability could allow an attacker to execute arbitrary code or cause denial of service by exploiting the JIT miscompilation flaw. The impact is rated high across confidentiality, integrity, and availability, meaning sensitive data could be exposed or altered, and system stability could be compromised.

Mitigation Recommendations

A fix is available and included in Mozilla Firefox version 150.0.3. Users and administrators should update affected Firefox installations to version 150.0.3 or later to remediate this vulnerability. No additional mitigation steps are indicated by the vendor advisory.

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Technical Details

Data Version
5.2
Assigner Short Name
mozilla
Date Reserved
2026-05-12T12:36:11.734Z
Cvss Version
null
State
PUBLISHED
Remediation Level
null
Vendor Advisory Urls
[{"url":"https://www.mozilla.org/security/advisories/mfsa2026-45/","vendor":"Mozilla"}]

Threat ID: 6a032959cbff5d8610e85ace

Added to database: 05/12/2026, 13:21:29 UTC

Last enriched: 07/15/2026, 08:14:13 UTC

Last updated: 07/31/2026, 19:23:00 UTC

Views: 120

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