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Status published
Unknown
CVE-2025-5270
SNI was sometimes unencrypted
Vulnerability Description
In certain cases, SNI could have been sent unencrypted even when encrypted DNS was enabled. This vulnerability was fixed in Firefox 139 and Thunderbird 139.
Impact Analysis
Refer to official advisory for detailed impact metrics.
Remediation
Ensure systems are updated to the latest vendor-supplied patch levels.
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Credits & Attribution
The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:
- xiulou
References
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CVE-2025-9186
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CVE-2025-9185
Memory safety bugs fixed in Firefox ESR 115.27, Firefox ESR 128.14, Thunderbird ESR 128.14, Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142
Unknown
0
CVE-2025-9184
Memory safety bugs fixed in Firefox ESR 140.2, Thunderbird ESR 140.2, Firefox 142 and Thunderbird 142
Unknown
0
CVE-2025-9183
Spoofing issue in the Address Bar component
Unknown
0
Affected Vendor
Mozilla
View all reports →Affected Software
Firefox, Thunderbird
Vulnerable Versions:
139
Timeline
Official Publish:
May 27th, 2025
Last Modified:
April 13th, 2026
Added to House:
July 22nd, 2026
CVSS Vectors
No vector data available
Weaknesses (CWE)
No CWE data available
MITRE ATT&CK TTPs
No associated TTPs found for this vulnerability.