How severe is CVE-2025-66028?

CVE-2025-66028 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.

Is CVE-2025-66028 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-66028?

CVE-2025-66028 affects Hackerbay Oneuptime. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-66028?

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

Does CVE-2025-66028 have an EU (EUVD) identifier?

Yes. CVE-2025-66028 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-199750.

When was CVE-2025-66028 published?

CVE-2025-66028 was published on 2025-11-26 and last updated on 2026-06-17.

CVE-2025-66028

CVE-2025-66028 is a high-severity vulnerability in Hackerbay Oneuptime with a CVSS 3.x base score of 8.2. 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-284.

Key facts

Severity: High (CVSS 3.x base score 8.2)
CVSS v4: 6.9
EPSS exploit prediction: 0% (23rd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-199750
Weakness: CWE-284
Affected product: Hackerbay Oneuptime
Published: 2025-11-26
Last modified: 2026-06-17

Description

OneUptime is a solution for monitoring and managing online services. Prior to version 8.0.5567, OneUptime is vulnerable to privilege escalation via Login Response Manipulation. During the login process, the server response included a parameter called isMasterAdmin. By intercepting and modifying this parameter value from false to true, it is possible to gain access to the admin dashboard interface. However, an attacker may be unable to view or interact with the data if they still do not have sufficient permissions. This issue has been patched in version 8.0.5567.

Frequently asked questions

What is CVE-2025-66028?: OneUptime is a solution for monitoring and managing online services. Prior to version 8.0.5567, OneUptime is vulnerable to privilege escalation via Login Response Manipulation. During the login process, the server response included a parameter called isMasterAdmin. By intercepting and modifying this parameter value from false to true, it is possible to gain access to the admin dashboard interface. However, an attacker may be unable to view or interact with the data if they still do not have sufficient permissions. This issue has been patched in version 8.0.5567.
How severe is CVE-2025-66028?: CVE-2025-66028 has a CVSS 3.x base score of 8.2, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity low, and availability none.
Is CVE-2025-66028 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (23rd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-66028?: CVE-2025-66028 affects Hackerbay Oneuptime. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-66028?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
Does CVE-2025-66028 have an EU (EUVD) identifier?: Yes. CVE-2025-66028 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-199750.
When was CVE-2025-66028 published?: CVE-2025-66028 was published on 2025-11-26 and last updated on 2026-06-17.

References

Affected products (1)

cpe:2.3:a:hackerbay:oneuptime:*:*:*:*:*:*:*:*

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