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.
CVSS Score
7.5
HIGH
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 139.0 |
Related Weaknesses (CWE)
References
- https://bugzilla.mozilla.org/show_bug.cgi?id=1910298Permissions Required
- https://www.mozilla.org/security/advisories/mfsa2025-42/Vendor Advisory
- https://www.mozilla.org/security/advisories/mfsa2025-45/
FAQ
What is CVE-2025-5270?
CVE-2025-5270 is a vulnerability with a CVSS score of 7.5 (HIGH). 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.
How severe is CVE-2025-5270?
CVE-2025-5270 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2025-5270?
Check the references section above for vendor advisories and patch information. Affected products include: Mozilla Firefox.