CVE-2026-16405: Vulnerability in Mozilla Firefox
CVE-2026-16405 is an information disclosure vulnerability in the Networking: WebSockets component of Mozilla Firefox. This issue was addressed and fixed in Firefox 153 and Firefox ESR 140.13. The vulnerability is considered low impact relative to other concurrent Firefox vulnerabilities fixed in these releases. Mozilla has released official security advisories confirming the fix and providing details on multiple vulnerabilities resolved in these versions.
AI Analysis
Technical Summary
The vulnerability identified as CVE-2026-16405 involves information disclosure through the WebSockets networking component in Mozilla Firefox. It was resolved in Firefox 153 and Firefox ESR 140.13 as part of a broader security update that addressed numerous vulnerabilities across various components including DOM, JavaScript engine, graphics, and sandbox escapes. The vendor advisory explicitly states the fix availability in these versions. No known exploits in the wild have been reported for this specific issue.
Potential Impact
Successful exploitation of this vulnerability could lead to limited information disclosure via the WebSockets component. The impact is rated low by Mozilla, indicating that the vulnerability does not allow for privilege escalation or remote code execution but could potentially expose some data. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 153 and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the issue. Since the vulnerability is fixed in these releases, no additional mitigation steps 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. This issue was addressed and fixed in Firefox 153 and Firefox ESR 140.13. The vulnerability is considered low impact relative to other concurrent Firefox vulnerabilities fixed in these releases. Mozilla has released official security advisories confirming the fix and providing details on multiple vulnerabilities resolved in these versions.
Affected software
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability identified as CVE-2026-16405 involves information disclosure through the WebSockets networking component in Mozilla Firefox. It was resolved in Firefox 153 and Firefox ESR 140.13 as part of a broader security update that addressed numerous vulnerabilities across various components including DOM, JavaScript engine, graphics, and sandbox escapes. The vendor advisory explicitly states the fix availability in these versions. No known exploits in the wild have been reported for this specific issue.
Potential Impact
Successful exploitation of this vulnerability could lead to limited information disclosure via the WebSockets component. The impact is rated low by Mozilla, indicating that the vulnerability does not allow for privilege escalation or remote code execution but could potentially expose some data. There are no reports of active exploitation in the wild.
Mitigation Recommendations
Mozilla has released official fixes for this vulnerability in Firefox 153 and Firefox ESR 140.13. Users and administrators should update to these versions or later to remediate the issue. Since the vulnerability is fixed in these releases, no additional mitigation steps 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: 07/21/2026, 13:13:42 UTC
Last updated: 07/21/2026, 13:13:42 UTC
Views: 2
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