Medium severity · published Sep 15, 2025
CVE-2025-6999
WatchGuard Firebox Authentication Portal Request Smuggling Vulnerability
6.9
CVSS
0.4%
EPSS
No
On KEV
Description
An HTTP Request Smuggling [CWE-444] vulnerability in the Authentication portal of WatchGuard Fireware OS allows a remote attacker to evade request parameter sanitation and perform a reflected self-Cross-Site Scripting (XSS) attack.
WatchGuard does not believe there is a practical exploit chain with a meaningful security impact for this vulnerability.
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 39% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
FO
Fireware OS · WatchGuard
12.0 before 12.11.3 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-6999
CVE.org
https://www.cve.org/CVERecord?id=CVE-2025-6999
psirt.watchguard.com
https://psirt.watchguard.com/CVE-2025-6999
www.watchguard.com
https://www.watchguard.com/wgrd-psirt/advisory/wgsa-2025-00014
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