CVE-2025-5270
HIGHCVSS 7.5/10EPSS 0.23%
Last modified
CVE-2025-5270 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. 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.. EPSS estimates a 0.23% chance of exploitation in the next 30 days.
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.
Metrics
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness Enumeration
Affected Software
| Vendor | Product | Versions |
|---|---|---|
| Mozilla | Firefox | < 139.0 |
References
Timeline
- Published
- Last Modified
- Status
- Modified
Frequently Asked Questions
What is 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.
How severe is CVE-2025-5270?
CVE-2025-5270 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.23% probability of exploitation in the next 30 days.
How do I fix CVE-2025-5270?
Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.
Are you affected by CVE-2025-5270?
Run a free Strix scan to check your systems for this vulnerability.
Scan your code nowSource: NVD / NIST