CVE-2026-8955: Vulnerability in Mozilla Firefox
CVE-2026-8955 is a privilege escalation vulnerability in the DOM: Workers component of Mozilla Firefox. This vulnerability was addressed and fixed in Firefox 151 and Firefox ESR 140.11. It has a high severity rating with a CVSS score of 8.8, indicating it could allow an attacker to gain elevated privileges. The vendor advisories confirm the issue and the availability of fixes in the specified Firefox versions.
AI Analysis
Technical Summary
CVE-2026-8955 is a high-severity privilege escalation vulnerability affecting the DOM: Workers component in Mozilla Firefox. The vulnerability allows an attacker to escalate privileges within the browser environment. It was fixed in Firefox 151 and Firefox ESR 140.11, as documented in Mozilla security advisories MFSA 2026-46 and MFSA 2026-48. The CVSS 3.1 base score is 8.8, reflecting 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 escalate privileges within the Firefox browser, potentially leading to unauthorized actions or access. The high CVSS score indicates significant impact on confidentiality, integrity, and availability of the affected system. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
This vulnerability has been fixed in Firefox 151 and Firefox ESR 140.11. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, manual patching is required. No additional mitigation steps are indicated by the vendor advisories.
CVE-2026-8955: Vulnerability in Mozilla Firefox
Description
CVE-2026-8955 is a privilege escalation vulnerability in the DOM: Workers component of Mozilla Firefox. This vulnerability was addressed and fixed in Firefox 151 and Firefox ESR 140.11. It has a high severity rating with a CVSS score of 8.8, indicating it could allow an attacker to gain elevated privileges. The vendor advisories confirm the issue and the availability of fixes in the specified Firefox versions.
CVSS v3.1
Score 8.8high
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-8955 is a high-severity privilege escalation vulnerability affecting the DOM: Workers component in Mozilla Firefox. The vulnerability allows an attacker to escalate privileges within the browser environment. It was fixed in Firefox 151 and Firefox ESR 140.11, as documented in Mozilla security advisories MFSA 2026-46 and MFSA 2026-48. The CVSS 3.1 base score is 8.8, reflecting 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 escalate privileges within the Firefox browser, potentially leading to unauthorized actions or access. The high CVSS score indicates significant impact on confidentiality, integrity, and availability of the affected system. However, there are no known exploits in the wild at this time.
Mitigation Recommendations
This vulnerability has been fixed in Firefox 151 and Firefox ESR 140.11. Users and administrators should update to these versions or later to remediate the issue. Since this is not a cloud service, manual patching is required. No additional mitigation steps are indicated by the vendor advisories.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-19T12:29:48.978Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-46/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-48/","vendor":"Mozilla"}]
Threat ID: 6a0c677bec166c07b0a993db
Added to database: 05/19/2026, 13:36:59 UTC
Last enriched: 05/26/2026, 20:41:22 UTC
Last updated: 07/31/2026, 19:23:00 UTC
Views: 118
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