CVE-2025-5270 (GCVE-0-2025-5270)

Vulnerability from cvelistv5 – Published: 2025-05-27 12:29 – Updated: 2026-04-13 14:30
VLAI?
Title
SNI was sometimes unencrypted
Summary
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.
Severity ?
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
CWE
  • CWE-319 - Cleartext Transmission of Sensitive Information
Assigner
References
Impacted products
Vendor Product Version
Mozilla Firefox Unaffected: 139 , ≤ * (rpm)
Create a notification for this product.
Credits
xiulou
Show details on NVD website
To clipboard 

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  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
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