Vulnerability in Hackerbay Oneuptime

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.

Published · last modified .

CVSS v3 metric

CVSS v3 base score 8.2 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:L/A:N.

EPSS exploit prediction

EPSS: 0.003 (20.6th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 20.6% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2025-66028: held from 0.003 to 0.003.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2025-66028?
CVE-2025-66028 is a high-severity vulnerability in Hackerbay Oneuptime, classified under Improper Access Control. CVSS score: 8.2/10. Published 2025-11-26.
How severe is CVE-2025-66028?
High severity. CVSS v3 base score is 8.2 out of 10.