CVE-2025-6432: Vulnerability in Mozilla Firefox
When Multi-Account Containers was enabled, DNS requests could have bypassed a SOCKS proxy when the domain name was invalid or the SOCKS proxy was not responding. This vulnerability was fixed in Firefox 140 and Thunderbird 140.
AI Analysis
Technical Summary
This vulnerability involves DNS requests bypassing a SOCKS proxy under certain conditions in Firefox when Multi-Account Containers is enabled. If the domain name was invalid or the SOCKS proxy was not responding, DNS requests could leak outside the proxy, potentially exposing user DNS queries. The flaw was addressed and fixed in Firefox 140 and Thunderbird 140 releases.
Potential Impact
The impact is primarily DNS leakage outside of a configured SOCKS proxy, which could reduce user privacy by exposing DNS queries to unintended observers. The CVSS score is high (8.6) due to network attack vector and confidentiality impact, but the Mozilla advisory rates the impact as low. There are no known exploits in the wild for this vulnerability.
Mitigation Recommendations
A fix for this vulnerability is available in Firefox 140 and Thunderbird 140. Users and administrators should update to these versions or later to remediate the issue. Since the vulnerability is fixed in official releases, no additional mitigation steps are required beyond applying the update.
CVE-2025-6432: Vulnerability in Mozilla Firefox
Description
When Multi-Account Containers was enabled, DNS requests could have bypassed a SOCKS proxy when the domain name was invalid or the SOCKS proxy was not responding. This vulnerability was fixed in Firefox 140 and Thunderbird 140.
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
This vulnerability involves DNS requests bypassing a SOCKS proxy under certain conditions in Firefox when Multi-Account Containers is enabled. If the domain name was invalid or the SOCKS proxy was not responding, DNS requests could leak outside the proxy, potentially exposing user DNS queries. The flaw was addressed and fixed in Firefox 140 and Thunderbird 140 releases.
Potential Impact
The impact is primarily DNS leakage outside of a configured SOCKS proxy, which could reduce user privacy by exposing DNS queries to unintended observers. The CVSS score is high (8.6) due to network attack vector and confidentiality impact, but the Mozilla advisory rates the impact as low. There are no known exploits in the wild for this vulnerability.
Mitigation Recommendations
A fix for this vulnerability is available in Firefox 140 and Thunderbird 140. Users and administrators should update to these versions or later to remediate the issue. Since the vulnerability is fixed in official releases, no additional mitigation steps are required beyond applying the update.
Technical Details
- Data Version
- 5.1
- Assigner Short Name
- mozilla
- Date Reserved
- 2025-06-20T14:51:37.854Z
- Cvss Version
- null
- State
- PUBLISHED
Threat ID: 685aa0274dc24046c1dc5ab2
Added to database: 6/24/2025, 12:55:03 PM
Last enriched: 4/14/2026, 11:52:07 AM
Last updated: 5/8/2026, 7:17:37 PM
Views: 127
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