CVE-2026-16388: Vulnerability in Mozilla Firefox
CVE-2026-16388 is a sandbox escape vulnerability in the DOM Networking component of Mozilla Firefox. This critical vulnerability allows an attacker to potentially break out of the browser's sandbox environment. It affects Firefox versions prior to 153 and was fixed in Firefox 153. The vulnerability has a CVSS score of 9.8, indicating a critical severity with high impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported. The vendor advisory confirms the fix is available in Firefox 153.
AI Analysis
Technical Summary
CVE-2026-16388 is a sandbox escape vulnerability located in the DOM Networking component of Mozilla Firefox. This flaw allows an attacker to escape the browser sandbox, potentially leading to full compromise of the affected system. The vulnerability was addressed and fixed in Firefox version 153. The CVSS v3.1 base score is 9.8 (critical), with attack vector network, low attack complexity, no privileges required, no user interaction, and impacts confidentiality, integrity, and availability at a high level. The Mozilla advisory confirms the fix and provides references to the associated bug report (Bug 2043845).
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the Firefox sandbox, potentially leading to arbitrary code execution with the privileges of the user running the browser. This could result in full system compromise, data theft, or system disruption. The vulnerability affects confidentiality, integrity, and availability at a high level. There are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox version 153. Users and administrators should update affected Firefox installations to version 153 or later to remediate this issue. Since this is not a cloud service, patching the client software is required. No additional mitigation steps are indicated by the vendor advisory.
CVE-2026-16388: Vulnerability in Mozilla Firefox
Description
CVE-2026-16388 is a sandbox escape vulnerability in the DOM Networking component of Mozilla Firefox. This critical vulnerability allows an attacker to potentially break out of the browser's sandbox environment. It affects Firefox versions prior to 153 and was fixed in Firefox 153. The vulnerability has a CVSS score of 9.8, indicating a critical severity with high impact on confidentiality, integrity, and availability. No known exploits in the wild have been reported. The vendor advisory confirms the fix is available in Firefox 153.
CVSS v3.1
Score 9.8critical
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16388 is a sandbox escape vulnerability located in the DOM Networking component of Mozilla Firefox. This flaw allows an attacker to escape the browser sandbox, potentially leading to full compromise of the affected system. The vulnerability was addressed and fixed in Firefox version 153. The CVSS v3.1 base score is 9.8 (critical), with attack vector network, low attack complexity, no privileges required, no user interaction, and impacts confidentiality, integrity, and availability at a high level. The Mozilla advisory confirms the fix and provides references to the associated bug report (Bug 2043845).
Potential Impact
Successful exploitation of this vulnerability could allow an attacker to escape the Firefox sandbox, potentially leading to arbitrary code execution with the privileges of the user running the browser. This could result in full system compromise, data theft, or system disruption. The vulnerability affects confidentiality, integrity, and availability at a high level. There are no known exploits in the wild at this time.
Mitigation Recommendations
Mozilla has released an official fix for this vulnerability in Firefox version 153. Users and administrators should update affected Firefox installations to version 153 or later to remediate this issue. Since this is not a cloud service, patching the client software is required. No additional mitigation steps are indicated by the vendor advisory.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:57:06.919Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"}]
Threat ID: 6a5f6cbe2a4a8d598926260a
Added to database: 07/21/2026, 12:57:34 UTC
Last enriched: 07/30/2026, 10:09:05 UTC
Last updated: 09/03/2026, 22:52:09 UTC
Views: 45
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