CVE-2025-69689 Overview
The Fan Control application version V251 contains an improper privilege handling vulnerability (CWE-269) in its Open File Dialog component. The dialog processes user-supplied paths with elevated permissions, which can be exploited by a local attacker to perform actions with administrator-level privileges. This privilege escalation vulnerability allows attackers with local access to escalate their privileges beyond their intended authorization level.
Critical Impact
Local attackers can leverage the improper privilege handling in the Open File Dialog to execute actions with administrator-level privileges, potentially leading to full system compromise.
Affected Products
- Fan Control V251
Discovery Timeline
- 2026-04-27 - CVE-2025-69689 published to NVD
- 2026-04-27 - Last updated in NVD database
Technical Details for CVE-2025-69689
Vulnerability Analysis
This vulnerability stems from improper privilege management in the Fan Control application's Open File Dialog functionality. When the application presents the file dialog to users, it fails to properly drop elevated privileges before processing user-supplied file paths. This architectural flaw allows operations triggered through the dialog to execute with the application's elevated context rather than the user's actual privilege level.
The vulnerability affects the local attack surface, requiring the attacker to have local access to the system where Fan Control is installed. No user interaction is required once the attacker has local access, and the scope is changed, meaning the vulnerability can affect resources beyond the vulnerable component's security scope.
Root Cause
The root cause is classified as CWE-269 (Improper Privilege Management). The Fan Control application runs with elevated privileges to access hardware components for fan control functionality. However, the Open File Dialog component inherits these elevated privileges and does not implement proper privilege separation or sandboxing when handling user-supplied paths. This allows user-controlled input to be processed in a privileged context.
Attack Vector
The attack vector is local, requiring an attacker to have access to a system running the vulnerable Fan Control V251 application. The attacker can exploit the Open File Dialog by supplying specially crafted file paths that, when processed by the privileged dialog component, perform actions at the administrator privilege level. This could include reading protected files, writing to restricted directories, or executing commands with elevated permissions.
The exploitation requires low privileges initially (a standard user account), but can result in high impact to confidentiality, integrity, and availability due to the scope change to administrator-level access.
Detection Methods for CVE-2025-69689
Indicators of Compromise
- Unusual file system access patterns from the Fan Control process, particularly accessing files or directories outside normal application scope
- Unexpected child processes spawned by Fan Control with elevated privileges
- Modifications to protected system files or registry keys attributed to the Fan Control application
Detection Strategies
- Monitor process execution chains for Fan Control application spawning unexpected child processes
- Implement file integrity monitoring on sensitive system directories to detect unauthorized modifications
- Enable Windows Security Event logging for privilege escalation events (Event ID 4672, 4673)
- Deploy endpoint detection rules that alert on Open File Dialog abuse patterns
Monitoring Recommendations
- Configure endpoint protection to monitor Fan Control application behavior for anomalous privilege usage
- Establish baseline behavior for the Fan Control application and alert on deviations
- Review Windows Event Logs for security events related to privilege escalation attempts
- Monitor for unauthorized access to protected file system locations by the Fan Control process
How to Mitigate CVE-2025-69689
Immediate Actions Required
- Assess all systems running Fan Control V251 for potential exploitation
- Consider temporarily uninstalling or disabling the Fan Control application until a patch is available
- Limit local access to systems running the vulnerable application to trusted users only
- Implement application allowlisting to prevent unauthorized executables from running
Patch Information
At the time of publication, users should monitor the FanControl Official Site and GitHub FanControl Releases for security updates addressing this vulnerability. The vulnerable version V251 is documented at GitHub FanControl Release V251.
Workarounds
- Run Fan Control with least-privilege principles where possible, though this may limit hardware access functionality
- Restrict local access to affected systems to only trusted administrators
- Implement network segmentation to limit lateral movement if exploitation occurs
- Consider using alternative fan control solutions until a security patch is released
# Example: Review installed Fan Control version on Windows
# Check Programs and Features or run from PowerShell
Get-ItemProperty HKLM:\Software\Microsoft\Windows\CurrentVersion\Uninstall\* | Where-Object {$_.DisplayName -like "*Fan Control*"} | Select-Object DisplayName, DisplayVersion
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
