CVE-2026-12303: Vulnerability in Mozilla Firefox
CVE-2026-12303 is an information disclosure vulnerability in Mozilla Firefox's Graphics: WebGPU component caused by incorrect boundary conditions. This flaw was fixed in Firefox version 152. The vulnerability has a moderate impact and a CVSS score of 4.3. It is part of a broader set of security fixes released in Firefox 152 and Thunderbird 152 addressing multiple memory safety, sandbox escape, and other issues. No known exploits are reported in the wild for this specific vulnerability.
AI Analysis
Technical Summary
CVE-2026-12303 is an information disclosure vulnerability due to incorrect boundary conditions in the Graphics: WebGPU component of Mozilla Firefox. This vulnerability could allow unauthorized disclosure of information. It was addressed and fixed in Firefox 152 and Thunderbird 152 as part of a comprehensive security update that also fixed multiple other high and moderate impact vulnerabilities. The CVSS 3.1 base score is 4.3, reflecting a network attack vector with low complexity, no privileges required, and user interaction needed, resulting in limited confidentiality impact without integrity or availability effects.
Potential Impact
The vulnerability allows information disclosure, which could lead to exposure of sensitive data handled by the WebGPU component. The impact is limited to confidentiality with no direct integrity or availability impact. There are no known active exploits in the wild for this vulnerability. The issue affects Firefox versions prior to 152.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 152 and Thunderbird 152. Users and administrators should update affected products to version 152 or later to remediate this issue. Since the fix is available and included in the official release, applying the update is the recommended mitigation. No additional vendor-recommended mitigations are necessary.
CVE-2026-12303: Vulnerability in Mozilla Firefox
Description
CVE-2026-12303 is an information disclosure vulnerability in Mozilla Firefox's Graphics: WebGPU component caused by incorrect boundary conditions. This flaw was fixed in Firefox version 152. The vulnerability has a moderate impact and a CVSS score of 4.3. It is part of a broader set of security fixes released in Firefox 152 and Thunderbird 152 addressing multiple memory safety, sandbox escape, and other issues. No known exploits are reported in the wild for this specific vulnerability.
CVSS v3.1
Score 4.3medium
Affected software
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Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-12303 is an information disclosure vulnerability due to incorrect boundary conditions in the Graphics: WebGPU component of Mozilla Firefox. This vulnerability could allow unauthorized disclosure of information. It was addressed and fixed in Firefox 152 and Thunderbird 152 as part of a comprehensive security update that also fixed multiple other high and moderate impact vulnerabilities. The CVSS 3.1 base score is 4.3, reflecting a network attack vector with low complexity, no privileges required, and user interaction needed, resulting in limited confidentiality impact without integrity or availability effects.
Potential Impact
The vulnerability allows information disclosure, which could lead to exposure of sensitive data handled by the WebGPU component. The impact is limited to confidentiality with no direct integrity or availability impact. There are no known active exploits in the wild for this vulnerability. The issue affects Firefox versions prior to 152.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox 152 and Thunderbird 152. Users and administrators should update affected products to version 152 or later to remediate this issue. Since the fix is available and included in the official release, applying the update is the recommended mitigation. No additional vendor-recommended mitigations are necessary.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-06-15T15:08:11.833Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-57/","vendor":"Mozilla"}]
Threat ID: 6a314c7e0b89be6888b4cc8b
Added to database: 06/16/2026, 13:15:42 UTC
Last enriched: 06/23/2026, 15:19:00 UTC
Last updated: 08/01/2026, 07:17:58 UTC
Views: 72
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