CVE-2025-6425
published 2025-06-24CVE-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
0.31%
22.7th 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
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| debian | firefox | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| debian | firefox-esr | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| debian | thunderbird | < firefox 140.0-1 (sid) | firefox 140.0-1 (sid) |
| mozilla | firefox | < 115.25.0 | 115.25.0 |
| mozilla | firefox | < 140.0 | 140.0 |
| mozilla | firefox | — | — |
| mozilla | firefox | >= 116.0 < 128.12.0 | 128.12.0 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1~deb11u1 | 1:128.12.0esr-1~deb11u1 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1~deb12u1 | 1:128.12.0esr-1~deb12u1 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1 | 1:128.12.0esr-1 |
| mozilla | thunderbird | >= 0 < 1:128.12.0esr-1 | 1:128.12.0esr-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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Ubuntu
Thunderbird vulnerabilities
vendor_ubuntu·2025-07-22
CVE-2025-4083 Thunderbird vulnerabilities
Title: Thunderbird vulnerabilities
Summary: Several security issues were fixed in Thunderbird.
Multiple security issues were discovered in Thunderbird. If a user were
tricked into opening a specially crafted website in a browsing context, an
attacker could potentially exploit these to cause a denial of service,
obtain sensitive information, bypass security restrictions, cross-site
tracing, or execute arbitrary code.
Instructions: This update uses a new upstream release, which includes additional bug
fixes. After a standard system update you need to restart thunderbird to
make all the necessary changes.
Red Hat
firefox: thunderbird: The WebCompat WebExtension shipped with Firefox exposed a persistent UUID
vendor_redhat·2025-06-24·CVSS 4.3
CVE-2025-6425 [MEDIUM] CWE-200 firefox: thunderbird: The WebCompat WebExtension shipped with Firefox exposed a persistent UUID
firefox: thunderbird: The WebCompat WebExtension shipped with Firefox exposed a persistent UUID
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 affects Firefox < 140, Firefox ESR < 115.25, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
A flaw was found in Firefox and Thunderbird. The Mozilla Foundation's Security Advisory describes the following issue: 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.
Statement: Red Ha
Debian
CVE-2025-6425: firefox - An attacker who enumerated resources from the WebCompat extension could have obt...
vendor_debian·2025·CVSS 4.3
CVE-2025-6425 [MEDIUM] CVE-2025-6425: firefox - An attacker who enumerated resources from the WebCompat extension could have obt...
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 affects Firefox < 140, Firefox ESR < 115.25, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
Scope: local
sid: resolved (fixed in 140.0-1)
Mozilla
Mozilla Foundation Security Advisory 2025-51: CVE-2025-6425
vendor_mozilla·CVSS 4.3
CVE-2025-6425 [MEDIUM] Mozilla Foundation Security Advisory 2025-51: CVE-2025-6425
Mozilla Foundation Security Advisory 2025-51
CVE: CVE-2025-6425
Product: Firefox
Impact: high
Fixed in: Firefox 140
Mozilla
Mozilla Foundation Security Advisory 2025-52: CVE-2025-6425
vendor_mozilla·CVSS 4.3
CVE-2025-6425 [MEDIUM] Mozilla Foundation Security Advisory 2025-52: CVE-2025-6425
Mozilla Foundation Security Advisory 2025-52
CVE: CVE-2025-6425
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 115.25
Mozilla
Mozilla Foundation Security Advisory 2025-54: CVE-2025-6425
vendor_mozilla·CVSS 4.3
CVE-2025-6425 [MEDIUM] Mozilla Foundation Security Advisory 2025-54: CVE-2025-6425
Mozilla Foundation Security Advisory 2025-54
CVE: CVE-2025-6425
Product: Thunderbird
Impact: high
Fixed in: Thunderbird 140
Mozilla
Mozilla Foundation Security Advisory 2025-55: CVE-2025-6425
vendor_mozilla·CVSS 4.3
CVE-2025-6425 [MEDIUM] Mozilla Foundation Security Advisory 2025-55: CVE-2025-6425
Mozilla Foundation Security Advisory 2025-55
CVE: CVE-2025-6425
Product: Thunderbird
Impact: moderate
Fixed in: Thunderbird 128.12
Mozilla
Mozilla Foundation Security Advisory 2025-53: CVE-2025-6425
vendor_mozilla·CVSS 4.3
CVE-2025-6425 [MEDIUM] Mozilla Foundation Security Advisory 2025-53: CVE-2025-6425
Mozilla Foundation Security Advisory 2025-53
CVE: CVE-2025-6425
Product: Firefox ESR
Impact: moderate
Fixed in: Firefox ESR 128.12
VulDB
Mozilla Firefox up to 139 WebCompat Extension information disclosure (EUVD-2025-19101 / Nessus ID 240338)
vuldb·2026-10-24·CVSS 4.3
CVE-2025-6425 [MEDIUM] Mozilla Firefox up to 139 WebCompat Extension information disclosure (EUVD-2025-19101 / Nessus ID 240338)
A vulnerability described as problematic has been identified in Mozilla Firefox up to 139. Affected is an unknown function of the component WebCompat Extension. The manipulation results in information disclosure.
This vulnerability is reported as CVE-2025-6425. The attack can be launched remotely. No exploit exists.
Upgrading the affected component is recommended.
GHSA
GHSA-2h3c-qrcw-962q: An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted bet
ghsa_unreviewed·2025-06-26
CVE-2025-6425 [MEDIUM] CWE-200 GHSA-2h3c-qrcw-962q: An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted bet
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 affects Firefox < 140, Firefox ESR < 115.25, and Firefox ESR < 128.12.
OSV
CVE-2025-6425: An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted bet
osv·2025-06-24·CVSS 4.3
CVE-2025-6425 [MEDIUM] CVE-2025-6425: An attacker who enumerated resources from the WebCompat extension could have obtained a persistent UUID that identified the browser, and persisted bet
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 affects Firefox < 140, Firefox ESR < 115.25, Firefox ESR < 128.12, Thunderbird < 140, and Thunderbird < 128.12.
No detection rules found.
No public exploits indexed.
https://bugzilla.mozilla.org/show_bug.cgi?id=1717672https://www.mozilla.org/security/advisories/mfsa2025-51/https://www.mozilla.org/security/advisories/mfsa2025-52/https://www.mozilla.org/security/advisories/mfsa2025-53/https://www.mozilla.org/security/advisories/mfsa2025-54/https://www.mozilla.org/security/advisories/mfsa2025-55/https://lists.debian.org/debian-lts-announce/2025/06/msg00029.htmlhttps://lists.debian.org/debian-lts-announce/2025/07/msg00002.html
2025-06-24
Published