CVE-2025-1239

CVE-2025-1239 is a medium-severity vulnerability with a CVSS 4.0 base score of 4.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-79.

Key facts

Description

Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the Blocked Sites list. This vulnerability requires an authenticated administrator session to a locally managed Firebox.This issue affects Fireware OS: from 12.0 through 12.5.12+701324, from 12.6 through 12.11.

Frequently asked questions

What is CVE-2025-1239?
Improper Neutralization of Input During Web Page Generation (XSS or 'Cross-site Scripting') vulnerability in WatchGuard Fireware OS allows Stored XSS via the Blocked Sites list. This vulnerability requires an authenticated administrator session to a locally managed Firebox.This issue affects Fireware OS: from 12.0 through 12.5.12+701324, from 12.6 through 12.11.
How severe is CVE-2025-1239?
CVE-2025-1239 has a CVSS 4.0 base score of 4.8, rated medium severity.
Is CVE-2025-1239 being actively exploited?
It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-1239?
Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-1239 have an EU (EUVD) identifier?
Yes. CVE-2025-1239 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-2095.
When was CVE-2025-1239 published?
CVE-2025-1239 was published on 2025-02-14 and last updated on 2026-06-17.

References

Other CWE-79 (Cross-site Scripting (XSS)) vulnerabilities

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