CVE-2026-16405: Vulnerability in Mozilla Firefox
CVE-2026-16405 is an information disclosure vulnerability in the Networking: WebSockets component of Mozilla Firefox. It allows unauthorized disclosure of information without user interaction or privileges. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13. The CVSS v3.1 base score is 7.5 (high severity), indicating a network attack vector with low complexity and no privileges or user interaction required. No known exploits in the wild have been reported. The vendor advisory confirms the fix is available in the stated versions.
AI Analysis
Technical Summary
CVE-2026-16405 is a high-severity information disclosure vulnerability affecting the WebSockets networking component in Mozilla Firefox. It allows an attacker to obtain sensitive information remotely without requiring privileges or user interaction. The vulnerability was addressed and fixed in Firefox 153 and Firefox ESR 140.13. The CVSS vector (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) indicates a remote attacker can exploit this flaw to gain high-impact confidentiality breaches without affecting integrity or availability. The Mozilla advisory confirms the fix and recommends updating to the fixed versions.
Potential Impact
Successful exploitation of this vulnerability could lead to unauthorized disclosure of sensitive information via the WebSockets component, potentially compromising user data confidentiality. There is no impact on integrity or availability. No active exploitation has been reported in the wild.
Mitigation Recommendations
A fix is available and has been released by Mozilla. Users and administrators should update to Firefox version 153 or later, or Firefox ESR 140.13 or later, to remediate this vulnerability. No additional mitigation actions are required beyond applying the official update.
CVE-2026-16405: Vulnerability in Mozilla Firefox
Description
CVE-2026-16405 is an information disclosure vulnerability in the Networking: WebSockets component of Mozilla Firefox. It allows unauthorized disclosure of information without user interaction or privileges. This vulnerability was fixed in Firefox 153 and Firefox ESR 140.13. The CVSS v3.1 base score is 7.5 (high severity), indicating a network attack vector with low complexity and no privileges or user interaction required. No known exploits in the wild have been reported. The vendor advisory confirms the fix is available in the stated versions.
CVSS v3.1
Score 7.5high
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
CVE-2026-16405 is a high-severity information disclosure vulnerability affecting the WebSockets networking component in Mozilla Firefox. It allows an attacker to obtain sensitive information remotely without requiring privileges or user interaction. The vulnerability was addressed and fixed in Firefox 153 and Firefox ESR 140.13. The CVSS vector (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N) indicates a remote attacker can exploit this flaw to gain high-impact confidentiality breaches without affecting integrity or availability. The Mozilla advisory confirms the fix and recommends updating to the fixed versions.
Potential Impact
Successful exploitation of this vulnerability could lead to unauthorized disclosure of sensitive information via the WebSockets component, potentially compromising user data confidentiality. There is no impact on integrity or availability. No active exploitation has been reported in the wild.
Mitigation Recommendations
A fix is available and has been released by Mozilla. Users and administrators should update to Firefox version 153 or later, or Firefox ESR 140.13 or later, to remediate this vulnerability. No additional mitigation actions are required beyond applying the official update.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- mozilla
- Date Reserved
- 2026-07-20T21:57:42.043Z
- 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: 6a5f6cc22a4a8d598926295e
Added to database: 07/21/2026, 12:57:38 UTC
Last enriched: 07/30/2026, 09:53:18 UTC
Last updated: 09/03/2026, 10:52:07 UTC
Views: 58
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