CVE-2025-5270

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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://bugzilla.mozilla.org/show_bug.cgi?id=1910298	Permissions Required
https://www.mozilla.org/security/advisories/mfsa2025-42/	Vendor Advisory
https://www.mozilla.org/security/advisories/mfsa2025-45/

Configurations

Configuration 1 (hide)

cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2025-05-27 13:15

Updated : 2026-06-17 09:47

NVD link : CVE-2025-5270

Mitre link : CVE-2025-5270

CVE.ORG link : CVE-2025-5270

JSON object : View

Products Affected

mozilla

firefox

CWE

CWE-319

Cleartext Transmission of Sensitive Information

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