CVE-2026-8958: Vulnerability in Mozilla Firefox
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI Analysis
Technical Summary
CVE-2026-8958 is an information disclosure and sandbox escape vulnerability affecting the Security: Process Sandboxing component in Mozilla Firefox. This flaw could potentially allow an attacker to bypass sandbox protections and access sensitive information. The issue was reported by Yaqoub Aldurayhim and is tracked under Bug 2034713. Mozilla fixed this vulnerability in Firefox 151 and Firefox ESR 140.11 as part of their May 19, 2026 security updates.
Potential Impact
The vulnerability allows information disclosure and sandbox escape, which could undermine the sandbox security model designed to isolate processes and limit the impact of exploits. The impact is rated moderate by Mozilla, indicating a significant but not critical risk. No active exploitation has been observed in the wild.
Mitigation Recommendations
A fix for this vulnerability is available. Users and administrators should update Mozilla Firefox to version 151 or later, or Firefox ESR to version 140.11 or later, to remediate this issue. No additional mitigation steps are required beyond applying the official update.
CVE-2026-8958: Vulnerability in Mozilla Firefox
Description
Information disclosure, sandbox escape in the Security: Process Sandboxing component. This vulnerability was fixed in Firefox 151, Firefox ESR 140.11, Thunderbird 151, and Thunderbird 140.11.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-8958 is an information disclosure and sandbox escape vulnerability affecting the Security: Process Sandboxing component in Mozilla Firefox. This flaw could potentially allow an attacker to bypass sandbox protections and access sensitive information. The issue was reported by Yaqoub Aldurayhim and is tracked under Bug 2034713. Mozilla fixed this vulnerability in Firefox 151 and Firefox ESR 140.11 as part of their May 19, 2026 security updates.
Potential Impact
The vulnerability allows information disclosure and sandbox escape, which could undermine the sandbox security model designed to isolate processes and limit the impact of exploits. The impact is rated moderate by Mozilla, indicating a significant but not critical risk. No active exploitation has been observed in the wild.
Mitigation Recommendations
A fix for this vulnerability is available. Users and administrators should update Mozilla Firefox to version 151 or later, or Firefox ESR to version 140.11 or later, to remediate this issue. No additional mitigation steps are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-05-19T12:29:53.304Z
- 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: 6a0c677bec166c07b0a993ea
Added to database: 5/19/2026, 1:36:59 PM
Last enriched: 5/19/2026, 1:54:44 PM
Last updated: 5/20/2026, 6:15:49 PM
Views: 13
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