How severe is CVE-2025-66571?

CVE-2025-66571 has a CVSS 4.0 base score of 9.3, rated critical severity.

Is CVE-2025-66571 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.

How do I fix CVE-2025-66571?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.

Does CVE-2025-66571 have an EU (EUVD) identifier?

Yes. CVE-2025-66571 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201274.

When was CVE-2025-66571 published?

CVE-2025-66571 was published on 2025-12-04 and last updated on 2026-06-17.

CVE-2025-66571

CVE-2025-66571 is a critical-severity vulnerability with a CVSS 4.0 base score of 9.3. 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-502.

Key facts

Severity: Critical (CVSS 4.0 base score 9.3)
EPSS exploit prediction: 1% (41st percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-201274
Weakness: CWE-502
Published: 2025-12-04
Last modified: 2026-06-17

Description

UNA CMS versions 9.0.0-RC1 - 14.0.0-RC4 contain a PHP object injection vulnerability in BxBaseMenuSetAclLevel.php where the profile_id POST parameter is passed to PHP unserialize() without proper handling, allowing remote, unauthenticated attackers to inject arbitrary PHP objects and potentially write and execute arbitrary PHP code.

Frequently asked questions

What is CVE-2025-66571?: UNA CMS versions 9.0.0-RC1 - 14.0.0-RC4 contain a PHP object injection vulnerability in BxBaseMenuSetAclLevel.php where the profile_id POST parameter is passed to PHP unserialize() without proper handling, allowing remote, unauthenticated attackers to inject arbitrary PHP objects and potentially write and execute arbitrary PHP code.
How severe is CVE-2025-66571?: CVE-2025-66571 has a CVSS 4.0 base score of 9.3, rated critical severity.
Is CVE-2025-66571 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (41st percentile), an estimate of the probability of exploitation in the next 30 days.
How do I fix CVE-2025-66571?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its critical severity, prioritise patching exposed systems.
Does CVE-2025-66571 have an EU (EUVD) identifier?: Yes. CVE-2025-66571 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-201274.
When was CVE-2025-66571 published?: CVE-2025-66571 was published on 2025-12-04 and last updated on 2026-06-17.

References

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