High severity7.5NVD Advisory· Published May 27, 2025· Updated Apr 13, 2026

CVE-2025-5270

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.

Affected products

Mozilla Corporation/Firefox
cpe:2.3:a:mozilla:firefox:*:*:*:*:*:*:*:*
Range: <139.0

Patches

No patches discovered yet.

Vulnerability mechanics

AI mechanics synthesis has not run for this CVE yet.

References

www.mozilla.org/security/advisories/mfsa2025-42/nvdVendor Advisory
bugzilla.mozilla.org/show_bug.cginvdPermissions Required
www.mozilla.org/security/advisories/mfsa2025-45/nvd

News mentions

No linked articles in our index yet.

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