cbcvebase.
CVE-2025-6425
published 2025-06-24

CVE-2025-6425: An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted between…

PriorityP419medium4.3CVSS 3.1
AVNACLPRNUIRSUCLINAN
EPSS
0.25%
16.2th percentile
An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted between containers and normal/private browsing mode, but not profiles. This vulnerability was fixed in Firefox 140, Firefox ESR 115.25, Firefox ESR 128.12, Thunderbird 140, and Thunderbird 128.12.

Affected

11 ranges
VendorProductVersion rangeFixed in
debianfirefox< firefox 140.0-1 (sid)firefox 140.0-1 (sid)
debianfirefox-esr< firefox 140.0-1 (sid)firefox 140.0-1 (sid)
debianthunderbird< firefox 140.0-1 (sid)firefox 140.0-1 (sid)
mozillafirefox< 115.25.0115.25.0
mozillafirefox< 140.0140.0
mozillafirefox
mozillafirefox>= 116.0 < 128.12.0128.12.0
mozillathunderbird>= 0 < 1:128.12.0esr-1~deb11u11:128.12.0esr-1~deb11u1
mozillathunderbird>= 0 < 1:128.12.0esr-1~deb12u11:128.12.0esr-1~deb12u1
mozillathunderbird>= 0 < 1:128.12.0esr-11:128.12.0esr-1
mozillathunderbird>= 0 < 1:128.12.0esr-11:128.12.0esr-1

CVSS provenance

nvdv3.14.3MEDIUMCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:L/I:N/A:N
osv4.3MEDIUM
vendor_debian4.3MEDIUM
vendor_redhat4.3MEDIUM
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