Which versions of UPSilon are affected by CVE-2025-66266?

Organizations using RupsMon.exe service executable in UPSilon 2000 face critical risk from CVE-2025-66266, a improper privilege management vulnerability rated CVSS 9.3.

How to fix or mitigate CVE-2025-66266?

Within 24 hours: Identify all affected systems and apply vendor patches immediately. Monitor vendor channels for patch availability.

UPSilon CVE-2025-66266

Q: What is the CVSS score of CVE-2025-66266?

CVE-2025-66266 has a CVSS 4.0 base score of 9.3 (Critical). CVSS vector: CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

CRITICAL

Improper Privilege Management (CWE-269)

2025-11-26 b7efe717-a805-47cf-8e9a-921fca0ce0ce

RCE Privilege Escalation

9.3

CVSS 4.0 · NVD

Severity by source

NVD PRIMARY

9.3 CRITICAL

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from NVD · only source for this CVE.

CVSS VectorNVD

CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:H/SI:H/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Local

Attack Complexity

Low

Privileges Required

None

User Interaction

None

Scope

Lifecycle Timeline

Analysis Generated

Mar 28, 2026 - 19:24 vuln.today

CVE Published

Nov 26, 2025 - 02:15 nvd

CRITICAL 9.3

DescriptionCVE.org

The RupsMon.exe service executable in UPSilon 2000 has insecure permissions, allowing the 'Everyone' group Full Control. A local attacker can replace the executable with a malicious binary to execute code with SYSTEM privileges or simply change the config path of the service to a command; starting and stopping the service to immediately achieve code execution and privilege escalation

AnalysisAI

The RupsMon.exe service executable in UPSilon 2000 has insecure permissions, allowing the 'Everyone' group Full Control. Rated critical severity (CVSS 9.3), this vulnerability is no authentication required, low attack complexity. No vendor patch available.

Technical ContextAI

This vulnerability is classified as Improper Privilege Management (CWE-269), which allows attackers to escalate privileges to gain unauthorized elevated access. The RupsMon.exe service executable in UPSilon 2000 has insecure permissions, allowing the 'Everyone' group Full Control. A local attacker can replace the executable with a malicious binary to execute code with SYSTEM privileges or simply change the config path of the service to a command; starting and stopping the service to immediately achieve code execution and privilege escalation

Affected ProductsAI

See vendor advisory for affected versions.

RemediationAI

No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Apply principle of least privilege, validate privilege transitions, implement proper role separation.