CVE-2025-5270highCWE-319

CVE-2025-5270: high-severity vulnerability in Mozilla Firefox

SNI was sometimes unencrypted

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21Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 7.5epss 0.3%
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:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Affected products
Mozilla · FirefoxMozilla · Thunderbird
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