CVE-2025-66005: InputPlumber Privilege Escalation Flaw

CVE-2025-66005 Overview

CVE-2025-66005 is an authorization bypass vulnerability affecting InputPlumber, a Linux input device management service. The vulnerability stems from a lack of proper authorization enforcement on the InputManager D-Bus interface. This security flaw allows local attackers to interact with the D-Bus interface without proper authentication, potentially leading to Denial-of-Service conditions, information disclosure, or privilege escalation within the context of the currently active user session.

Critical Impact
Unauthenticated local attackers can exploit the missing D-Bus authorization to escalate privileges, leak sensitive information, or cause service disruption within the active user session.

Affected Products

InputPlumber versions prior to v0.63.0
Linux systems running vulnerable InputPlumber D-Bus services
openSUSE distributions with affected InputPlumber packages

Discovery Timeline

2026-01-09 - openSUSE Security Advisory published
2026-01-14 - CVE CVE-2025-66005 published to NVD
2026-01-14 - Last updated in NVD database

Technical Details for CVE-2025-66005

Vulnerability Analysis

This vulnerability is classified under CWE-863 (Incorrect Authorization), indicating that the InputPlumber D-Bus service fails to properly verify whether a requesting entity has sufficient privileges to perform the requested actions on the InputManager interface.

D-Bus is an inter-process communication (IPC) mechanism commonly used in Linux desktop environments to allow applications to communicate with system services. The InputManager interface in InputPlumber handles input device management operations. Without proper authorization checks, any local process can send commands to this interface, regardless of the user's actual permissions.

The attack requires local access and some user interaction, but does not require prior authentication to the vulnerable service. Successful exploitation can result in complete compromise of confidentiality, integrity, and availability within the user session context.

Root Cause

The root cause of this vulnerability is the absence of authorization policy enforcement on the InputManager D-Bus interface. D-Bus services should implement policy configurations (typically via polkit or D-Bus policy files) to restrict which users or processes can invoke specific methods. In InputPlumber versions before v0.63.0, these authorization checks were not implemented, allowing unrestricted access to sensitive interface methods.

Attack Vector

The attack is local in nature and requires the attacker to have access to the D-Bus session bus. An attacker can exploit this vulnerability by:

Connecting to the user's session D-Bus
Sending unauthorized method calls to the InputManager interface
Manipulating input device configurations to gain elevated privileges or exfiltrate session information
Causing Denial-of-Service by disrupting input device management

The vulnerability requires user interaction (such as having an active session) but no special privileges beyond local access to the system.

Detection Methods for CVE-2025-66005

Indicators of Compromise

Unexpected D-Bus method calls to the InputManager interface from unauthorized processes
Unusual input device configuration changes logged by system services
Abnormal process activity interacting with InputPlumber D-Bus endpoints
Session-level privilege escalation attempts detected in audit logs

Detection Strategies

Monitor D-Bus traffic for unauthorized method invocations on InputPlumber interfaces using tools like dbus-monitor
Implement audit rules to track access to InputPlumber configuration files and D-Bus endpoints
Deploy endpoint detection solutions capable of identifying anomalous IPC activity within user sessions
Review system logs for InputPlumber service crashes or unexpected restarts indicating DoS attempts

Monitoring Recommendations

Enable verbose logging for D-Bus services to capture method call details
Configure SentinelOne agents to monitor for local privilege escalation patterns
Establish baseline behavior for InputPlumber D-Bus interactions and alert on deviations
Integrate SIEM alerts for CWE-863 related attack patterns in Linux environments

How to Mitigate CVE-2025-66005

Immediate Actions Required

Upgrade InputPlumber to version v0.63.0 or later immediately
Review D-Bus policies for any custom InputPlumber configurations
Restrict local user access on multi-user systems until patching is complete
Monitor for suspicious D-Bus activity targeting InputPlumber interfaces

Patch Information

The vulnerability has been addressed in InputPlumber version v0.63.0, which implements proper authorization checks on the InputManager D-Bus interface. System administrators should update to this version or later to remediate the vulnerability. Additional details are available in the openSUSE Security Advisory and the SUSE Bug Report.

Workarounds

Restrict D-Bus access to the InputPlumber service using custom polkit policies until the patch can be applied
Limit local user sessions on affected systems to trusted users only
Disable the InputPlumber service temporarily if input device management is not critical to operations
Implement network segmentation to reduce exposure on multi-user systems

bash

# Temporary workaround: Restrict D-Bus access to InputPlumber
# Create a polkit rule to limit access (example path may vary)
cat > /etc/polkit-1/rules.d/99-inputplumber-restrict.rules << 'EOF'
polkit.addRule(function(action, subject) {
    if (action.id.indexOf("org.inputplumber") === 0) {
        return polkit.Result.AUTH_ADMIN;
    }
});
EOF

# Restart polkit to apply changes
systemctl restart polkit