Vulnerability · CVE-2025-4804
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the spamBlocker module.
Published May 16, 2025 · catalog updated Aug 8, 2026 · WatchGuard Fireware OS
Check if you run it
No confirmed exploitation is on record for CVE-2025-4804. EPSS is 0.46%. Act only if a listed version of WatchGuard Fireware OS is installed.
Gaps on this record
- No vendor fix or required action is stored. Compare the linked advisory before you change production.
- Severity
- Medium4.8
- Known exploitation
- Not in CISA/VulnCheck KEV
- EPSS
- 0.46%
- Remediation
- Version ranges on file
- Affected products
- vendor WatchGuard Fireware OS 12.5 <12.5.13
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the spamBlocker module. This vulnerability requires an authenticated administrator session to a locally managed Firebox.
Are you affected?
Enter the version you run. The result uses only the ranges stored on this record.
The check returns affected, not affected, or incomplete. It does not guess a version that is missing from the record.
- vendor WatchGuard Fireware OS 12.5 <12.5.1312.5 <12.5.13
How to fix CVE-2025-4804
Recommended remediation
Affected version ranges suggest a fixed boundary. Verify against the vendor advisory for your release.
Official advisories
What to do
Three questions, each answered from this record only. Confirm the vendor advisory before you patch.
Should you patch?
No confirmed exploitation is on record for CVE-2025-4804. EPSS is 0.46%. Act only if a listed version of WatchGuard Fireware OS is installed.
Which versions are affected?
Compare what you have installed with WatchGuard Fireware OS 12.5 <12.5.13 12.5 <12.5.13. Compare the installed version with the linked vendor advisory before you change production.
What should an analyst verify?
No weakness class is stored. EPSS 0.46%. There is no CISA KEV listing. No Exploit-DB or Metasploit reference is linked. Use the source links for the original advisory.
Code
The project this record applies to. Exploit listings stay in References.
No public source repository is identified for this product.
Timeline
Detection, updates, and resolution for this record.
May 16, 2025 · EUVD
Detected
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the spamBlocker module. This vulnerability requires an authenticated administrator session to a locally managed Firebox.
Aug 8, 2026 · EUVD
Updated
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the spamBlocker module. This vulnerability requires an authenticated administrator session to a locally managed Firebox.
Sources
- CVE.orgVulnerability recordCVE-2025-4804
Official CVE identifier
cve.org - FIRST EPSSExploitation probabilityCVE-2025-4804
30-day exploitation probability 0.5%
first.org - EUVDVulnerability recordEUVD-2025-15550
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the spamBlocker module. This vulnerability requires an authenticated administrator session to a locally managed Firebox.
euvd.enisa.europa.eu
References
Freshness
Last verified in this catalog Oct 18, 2026. Significant claims (KEV, EPSS, CVSS, affected ranges) come from the source rows above — open the original publisher for the authoritative advisory.