CVE-2024-38260: Windows Server 2008 RCE Vulnerability

CVE-2024-38260 Overview

CVE-2024-38260 is a remote code execution vulnerability in the Windows Remote Desktop Licensing Service. The flaw affects every currently supported Windows Server release from 2008 R2 SP1 through 2022 23H2. An authenticated attacker with low privileges can send crafted network traffic to the licensing service and execute arbitrary code in its context. Microsoft attributes the issue to [CWE-908: Use of Uninitialized Resource], indicating the service consumes memory before it is properly initialized. Successful exploitation compromises confidentiality, integrity, and availability of the affected server. The vulnerability was published to the National Vulnerability Database on September 10, 2024.

Critical Impact
An authenticated network attacker can execute arbitrary code on servers running the Remote Desktop Licensing role, leading to full system compromise across supported Windows Server versions.

Affected Products

Microsoft Windows Server 2008 R2 SP1, 2012, and 2012 R2
Microsoft Windows Server 2016 and 2019
Microsoft Windows Server 2022 and 2022 23H2

Discovery Timeline

2024-09-10 - CVE-2024-38260 published to NVD and addressed in Microsoft's September 2024 Patch Tuesday release
2026-08-10 - Last updated in the NVD database

Technical Details for CVE-2024-38260

Vulnerability Analysis

The Remote Desktop Licensing Service (lserver.dll / LicenseServer) issues, tracks, and manages RDS client access licenses on Windows Server. CVE-2024-38260 resides in this service and enables remote code execution when an authenticated attacker submits crafted licensing requests. The attack requires network access to the licensing endpoint but no user interaction. Because the licensing service typically runs with elevated privileges, code execution here can pivot to full administrative control of the host. Domain environments that centralize the RD Licensing role expose additional lateral-movement surface.

Root Cause

Microsoft maps the defect to [CWE-908: Use of Uninitialized Resource]. The service processes licensing protocol messages that reference memory or state before it has been fully initialized. An attacker who controls the contents referenced by the uninitialized resource can steer execution flow, corrupt internal state, or trigger memory disclosure that enables code execution.

Attack Vector

Exploitation requires network reachability to the Remote Desktop Licensing endpoint and valid credentials for authentication. No user interaction is needed. The attacker sends malformed licensing protocol traffic that induces the service to operate on uninitialized memory. See the Microsoft CVE-2024-38260 Advisory for protocol-level details. No public proof-of-concept exploit is available at the time of writing, and the CVE is not listed in the CISA Known Exploited Vulnerabilities catalog. The EPSS model places the probability of exploitation in the wild at approximately 1.62%.

Detection Methods for CVE-2024-38260

Indicators of Compromise

Unexpected crashes, restarts, or hangs of the TermServLicensing service or lserver.dll on RD Licensing hosts.
Anomalous inbound connections to TCP port 135 (RPC) and dynamic RPC ports on servers hosting the RD Licensing role.
New or unsigned child processes spawned by svchost.exe hosting the licensing service.
Creation of scheduled tasks, services, or accounts on RD Licensing servers shortly after inbound RPC activity.

Detection Strategies

Monitor Windows Event Log sources Microsoft-Windows-TerminalServices-Licensing and application error logs for service faults referencing lserver.dll.
Alert on process-tree anomalies where the RD Licensing service host spawns shells, script interpreters, or LOLBins such as cmd.exe, powershell.exe, or rundll32.exe.
Correlate authenticated RPC sessions to the licensing endpoint against expected RD Session Host inventory.

Monitoring Recommendations

Inventory every server with the Remote Desktop Licensing role installed and confirm patch level against the September 2024 update baseline.
Enable network telemetry (NetFlow, Zeek, or Windows Firewall logs) for traffic destined to the licensing service.
Track successful and failed authentication events immediately preceding licensing service errors to identify probing.

How to Mitigate CVE-2024-38260

Immediate Actions Required

Apply the Microsoft September 2024 security updates to all affected Windows Server versions hosting the Remote Desktop Licensing role.
Restrict network access to the licensing service to known RD Session Host and RD Connection Broker systems using host and network firewalls.
Audit accounts permitted to authenticate to RD Licensing servers and remove unnecessary access.
Prioritize patching internet-exposed or DMZ-hosted licensing servers first.

Patch Information

Microsoft released fixes for CVE-2024-38260 on September 10, 2024. Refer to the Microsoft CVE-2024-38260 Advisory for the specific KB article and update package that applies to each Windows Server build, including Server 2008 R2 SP1, 2012, 2012 R2, 2016, 2019, 2022, and 2022 23H2.

Workarounds

If patching must be deferred, uninstall the Remote Desktop Licensing role on hosts that do not require it.
Block inbound RPC traffic to the licensing service from untrusted network segments using Windows Firewall or perimeter ACLs.
Enforce network-level authentication and segmentation so only management and RDS infrastructure hosts can reach the licensing endpoint.

bash

# Example: restrict inbound RPC endpoint mapper access to a trusted subnet
New-NetFirewallRule -DisplayName "Restrict RD Licensing RPC" `
  -Direction Inbound -Protocol TCP -LocalPort 135 `
  -RemoteAddress 10.10.20.0/24 -Action Allow

New-NetFirewallRule -DisplayName "Block RD Licensing RPC (default)" `
  -Direction Inbound -Protocol TCP -LocalPort 135 `
  -Action Block