CVE-2025-15552: LAPSWebUI Privilege Escalation Vulnerability

CVE-2025-15552 Overview

CVE-2025-15552 is an Insufficient Session Expiration vulnerability affecting Truesec's LAPSWebUI before version 2.4. This security flaw allows an attacker with access to a workstation to escalate their privileges through the disclosure of local administrator passwords. The vulnerability stems from improper session management (CWE-613), where sessions remain valid for extended periods, creating a window of opportunity for attackers to hijack active sessions or exploit cached credentials.

Critical Impact

An attacker with local workstation access can leverage excessively long session lifetimes to obtain local administrator passwords, enabling privilege escalation across the network environment.

Affected Products

• Truesec LAPSWebUI versions prior to 2.4

Discovery Timeline

• 2026-03-16 - CVE CVE-2025-15552 published to NVD
• 2026-03-16 - Last updated in NVD database

Technical Details for CVE-2025-15552

Vulnerability Analysis

This vulnerability is classified under CWE-613 (Insufficient Session Expiration), which occurs when a web application does not adequately terminate user sessions within an appropriate timeframe. In the context of LAPSWebUI, an application designed to manage Local Administrator Password Solution (LAPS) credentials, this oversight creates significant security implications.

The attack requires local access to a workstation and some user interaction, making it a more targeted attack scenario. However, the potential impact is substantial—successful exploitation enables an attacker to obtain local administrator passwords, which can then be leveraged to escalate privileges horizontally across multiple systems or vertically to domain-level access. The scope extends beyond the vulnerable component, potentially affecting the confidentiality and integrity of other systems managed through LAPS.

Root Cause

The root cause of this vulnerability lies in the application's session management configuration. LAPSWebUI versions prior to 2.4 implement session lifetimes that exceed security best practices, allowing authenticated sessions to persist for extended durations. This design flaw means that even after a legitimate user has finished their administrative tasks, their session remains valid and potentially exploitable.

When a user accesses LAPS passwords through the web interface, the session cookie remains active long after it should have been invalidated. An attacker with physical or remote access to the same workstation can leverage this persistent session to access the LAPS interface and retrieve local administrator passwords without needing to authenticate.

Attack Vector

The attack vector is local, requiring the attacker to have some form of access to a workstation where LAPSWebUI sessions have been established. The exploitation scenario typically involves:

1. A legitimate user authenticates to LAPSWebUI and retrieves local administrator passwords
2. The user completes their task but the session remains active due to insufficient expiration controls
3. An attacker gains access to the same workstation (physically or through another compromise)
4. The attacker leverages the still-valid session to access LAPSWebUI without authentication
5. The attacker retrieves local administrator passwords for target systems

The vulnerability requires some level of user interaction and specific preconditions to be met, making mass exploitation unlikely. However, in targeted attacks against organizations using LAPS, this vulnerability provides a reliable path to privilege escalation. For additional technical details, refer to the ReverseC Advisory on Session Lifetime.

Detection Methods for CVE-2025-15552

Indicators of Compromise

• Multiple LAPS password queries from the same session over an unusually long time span
• Session activity occurring hours after the original authentication event
• LAPS password access patterns that deviate from normal administrative workflows
• Browser session cookies for LAPSWebUI persisting beyond expected timeframes

Detection Strategies

• Monitor LAPSWebUI access logs for sessions that remain active beyond normal business hours or expected session durations
• Implement alerting on LAPS password retrievals that occur without corresponding recent authentication events
• Correlate workstation access logs with LAPSWebUI session activity to identify potential session hijacking
• Deploy endpoint detection to identify unauthorized access to browser session storage containing LAPSWebUI cookies

Monitoring Recommendations

• Enable verbose logging for LAPSWebUI authentication and password retrieval events
• Implement session duration monitoring and alert on sessions exceeding defined thresholds
• Monitor for concurrent session usage from different network locations or user contexts
• Review LAPS password access patterns regularly to identify anomalous behavior

How to Mitigate CVE-2025-15552

Immediate Actions Required

• Upgrade LAPSWebUI to version 2.4 or later immediately
• Force termination of all existing LAPSWebUI sessions following the upgrade
• Review LAPS password access logs for any suspicious session activity prior to patching
• Implement browser policies that clear session data upon browser close

Patch Information

The vulnerability has been addressed in LAPSWebUI version 2.4. Organizations should upgrade to this version or later to remediate the insufficient session expiration issue. Detailed information about the fix is available in the ReverseC Advisory on Session Lifetime.

Workarounds

• Configure web application firewall rules to enforce maximum session durations for LAPSWebUI
• Implement browser group policies that automatically clear cookies and session data when browsers are closed
• Restrict LAPSWebUI access to dedicated administrative workstations with strong physical security controls
• Deploy idle timeout scripts that force browser session termination after periods of inactivity

For environments where immediate patching is not feasible, consider implementing application-level session timeouts through a reverse proxy configuration:

# Example nginx configuration for session timeout enforcement
# Add to LAPSWebUI reverse proxy configuration
location /lapswebui/ {
    proxy_pass http://lapswebui-backend;
    proxy_cookie_path / "/; Max-Age=900; Secure; HttpOnly";
    proxy_read_timeout 900s;
}