CVE-2026-16391: Vulnerability in Mozilla Firefox
CVE-2026-16391 is an information disclosure vulnerability in the Storage: IndexedDB component of Mozilla Firefox. This flaw allows unauthorized access to sensitive information. The vulnerability was fixed in Firefox 153 and Firefox ESR 140.13. It has a high severity rating with a CVSS score of 7.5. There are no known exploits in the wild. Mozilla has officially addressed this issue in the stated fixed versions.
AI Analysis
Technical Summary
CVE-2026-16391 is an information disclosure vulnerability classified under CWE-200 affecting the Storage: IndexedDB component in Mozilla Firefox. The vulnerability allows unauthorized disclosure of information, potentially compromising user data confidentiality. It was resolved in Firefox 153 and Firefox ESR 140.13. The CVSS v3.1 base score is 7.5, indicating high severity, with an attack vector of network, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality. The vendor advisory confirms the fix availability and no known active exploitation.
Potential Impact
Successful exploitation of this vulnerability could lead to unauthorized disclosure of sensitive information stored or accessible via the IndexedDB component in Firefox. This compromises user privacy and data confidentiality but does not affect integrity or availability. No known exploits have been observed in the wild at this time.
Mitigation Recommendations
This vulnerability is fixed in Firefox 153 and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the issue. Since an official fix is available, applying the update is the recommended mitigation. No additional vendor-recommended mitigations are necessary.
CVE-2026-16391: Vulnerability in Mozilla Firefox
Description
CVE-2026-16391 is an information disclosure vulnerability in the Storage: IndexedDB component of Mozilla Firefox. This flaw allows unauthorized access to sensitive information. The vulnerability was fixed in Firefox 153 and Firefox ESR 140.13. It has a high severity rating with a CVSS score of 7.5. There are no known exploits in the wild. Mozilla has officially addressed this issue in the stated fixed versions.
CVSS v3.1
Score 7.5high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16391 is an information disclosure vulnerability classified under CWE-200 affecting the Storage: IndexedDB component in Mozilla Firefox. The vulnerability allows unauthorized disclosure of information, potentially compromising user data confidentiality. It was resolved in Firefox 153 and Firefox ESR 140.13. The CVSS v3.1 base score is 7.5, indicating high severity, with an attack vector of network, low attack complexity, no privileges required, no user interaction, and high impact on confidentiality. The vendor advisory confirms the fix availability and no known active exploitation.
Potential Impact
Successful exploitation of this vulnerability could lead to unauthorized disclosure of sensitive information stored or accessible via the IndexedDB component in Firefox. This compromises user privacy and data confidentiality but does not affect integrity or availability. No known exploits have been observed in the wild at this time.
Mitigation Recommendations
This vulnerability is fixed in Firefox 153 and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the issue. Since an official fix is available, 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
- 2026-07-20T21:57:12.625Z
- Cvss Version
- null
- State
- PUBLISHED
- Remediation Level
- null
- Vendor Advisory Urls
- [{"url":"https://www.mozilla.org/security/advisories/mfsa2026-68/","vendor":"Mozilla"},{"url":"https://www.mozilla.org/security/advisories/mfsa2026-70/","vendor":"Mozilla"}]
Threat ID: 6a5f6cc12a4a8d5989262912
Added to database: 07/21/2026, 12:57:37 UTC
Last enriched: 07/30/2026, 10:08:27 UTC
Last updated: 09/03/2026, 10:52:07 UTC
Views: 92
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