Vulnerability · NVD

CVE-2025-5266

CVE-2025-5266, medium severity (CVSS 4.3): 1 tracked app concerned, all fixed or indeterminable on their current version.

Severity (CVSS): 4.3
Exploitation: -
Tracked apps: 1
Still exposed: 0

Published on 2025-05-27

Script elements loading cross-origin resources generated load and error events which leaked information enabling XS-Leaks attacks. This vulnerability was fixed in Firefox 139, Firefox ESR 128.11, Thunderbird 139, and Thunderbird 128.11.

Attack vector : Network No privileges required

Show raw CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N

Tracked apps referencing this CVE

For each app: the affected range, the fixing version, and where the tracked app stands today.

Mozilla Firefox Windows winget:Mozilla.Firefox

Affected <128.11.0 Fixed in 128.11.0 Latest tracked 157.0 patched

Observed affected builds (90)

128.0.3 128.0.2 128.0 127.0.2 127.0.1 127.0 126.0.1 126.0 125.0.3 125.0.2 125.0.1 124.0.2 124.0.1 124.0 123.0.1 123.0 122.0.1 122.0 121.0.1 121.0 120.0.1 120.0 119.0.1 119.0 118.0.2 118.0.1 118.0 117.0.1 117.0 116.0.3 +60 · see history

Vulnerable CPE configurations (2)

Vendor	Product	Platform	Versions	CPE 2.3 URI
mozilla	firefox All platforms (wildcard)	All platforms (wildcard)	<128.11.0	cpe:2.3:a:mozilla:firefox:::::esr:::*
mozilla	firefox All platforms (wildcard)	All platforms (wildcard)	<139.0	cpe:2.3:a:mozilla:firefox:::::-:::*

View on NVD ↗ Advisory · www.mozilla.org

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