CVE-2026-74984: Vulnerability in Mozilla Firefox
CVE-2026-74984 is a race condition vulnerability in the JavaScript Engine component of Mozilla Firefox. This flaw was addressed and fixed in Firefox version 154 and Firefox ESR 153.1, as well as Thunderbird 154 and Thunderbird 153.1. The vulnerability has a CVSS v3.1 score of 6.8, indicating a medium severity level. It allows an attacker to potentially cause a high impact on confidentiality and integrity but requires high attack complexity and user interaction. No known exploits are reported in the wild at this time.
AI Analysis
Technical Summary
CVE-2026-74984 is a race condition vulnerability identified in the JavaScript Engine component of Mozilla Firefox. Race conditions occur when multiple threads or processes access shared data concurrently, leading to unpredictable behavior. This vulnerability was fixed in Firefox 154 and Firefox ESR 153.1. The CVSS score of 6.8 reflects a network attack vector with high complexity, no privileges required, and user interaction needed. The impact includes high confidentiality and integrity impacts but no availability impact. The vendor advisory confirms the fix availability in Firefox 154 and related Thunderbird versions.
Potential Impact
Successful exploitation of this race condition could lead to unauthorized disclosure or modification of information within the JavaScript engine context, impacting confidentiality and integrity. The attack complexity is high and requires user interaction, which reduces the likelihood of exploitation. There are no reports of active exploitation in the wild. The vulnerability does not affect availability.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 154 and Firefox ESR 153.1. Users and administrators should update affected Firefox and Thunderbird installations to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official update.
CVE-2026-74984: Vulnerability in Mozilla Firefox
Description
CVE-2026-74984 is a race condition vulnerability in the JavaScript Engine component of Mozilla Firefox. This flaw was addressed and fixed in Firefox version 154 and Firefox ESR 153.1, as well as Thunderbird 154 and Thunderbird 153.1. The vulnerability has a CVSS v3.1 score of 6.8, indicating a medium severity level. It allows an attacker to potentially cause a high impact on confidentiality and integrity but requires high attack complexity and user interaction. No known exploits are reported in the wild at this time.
CVSS v3.1
Score 6.8medium
Affected software
Mozilla
Firefox
Mozilla
Thunderbird
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-74984 is a race condition vulnerability identified in the JavaScript Engine component of Mozilla Firefox. Race conditions occur when multiple threads or processes access shared data concurrently, leading to unpredictable behavior. This vulnerability was fixed in Firefox 154 and Firefox ESR 153.1. The CVSS score of 6.8 reflects a network attack vector with high complexity, no privileges required, and user interaction needed. The impact includes high confidentiality and integrity impacts but no availability impact. The vendor advisory confirms the fix availability in Firefox 154 and related Thunderbird versions.
Potential Impact
Successful exploitation of this race condition could lead to unauthorized disclosure or modification of information within the JavaScript engine context, impacting confidentiality and integrity. The attack complexity is high and requires user interaction, which reduces the likelihood of exploitation. There are no reports of active exploitation in the wild. The vulnerability does not affect availability.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 154 and Firefox ESR 153.1. Users and administrators should update affected Firefox and Thunderbird installations to these versions or later to remediate the issue. No additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-08-17T11:59:15.390Z
- 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: 6a84550fc6e8be033236775e
Added to database: 08/18/2026, 12:50:23 UTC
Last enriched: 09/11/2026, 21:48:07 UTC
Last updated: 10/02/2026, 10:14:11 UTC
Views: 46
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