CVE-2024-30075 Overview
CVE-2024-30075 is a remote code execution vulnerability in the Windows Link Layer Topology Discovery (LLTD) Protocol. Microsoft disclosed the flaw on June 11, 2024 as part of its monthly security update cycle. The vulnerability affects Windows Server 2008 systems and is classified as a heap-based buffer overflow [CWE-122].
An attacker on an adjacent network can trigger the flaw by sending crafted LLTD traffic that a user must interact with. Successful exploitation grants full control over confidentiality, integrity, and availability of the target host.
Critical Impact
Successful exploitation allows an adjacent-network attacker to execute arbitrary code on affected Windows Server 2008 hosts, leading to complete system compromise.
Affected Products
- Microsoft Windows Server 2008 SP2 (x64)
- Microsoft Windows Server 2008 SP2 (x86)
- Microsoft Windows Server 2008 R2 SP1 (x64)
Discovery Timeline
- 2024-06-11 - CVE-2024-30075 published to NVD
- 2026-07-20 - Last updated in NVD database
Technical Details for CVE-2024-30075
Vulnerability Analysis
The Link Layer Topology Discovery Protocol enables Windows systems to discover and map devices on a local network segment. LLTD operates at the data link layer and processes Ethernet frames with EtherType 0x88D9. The protocol relies on the lltdio.sys and lltdsvc.dll components to parse topology discovery messages.
The vulnerability is a heap-based buffer overflow [CWE-122] in the LLTD parsing logic. Crafted protocol messages cause the service to write beyond an allocated heap buffer. This condition corrupts adjacent heap metadata and can be leveraged to redirect execution flow.
Exploitation requires user interaction and adjacent-network access. An attacker must be on the same broadcast domain because LLTD frames do not route across Layer 3 boundaries. This constraint limits remote exploitation but keeps risk elevated on flat enterprise LANs and shared Wi-Fi segments.
Root Cause
The root cause is improper size validation of attacker-controlled fields within LLTD topology discovery frames. The parser allocates a fixed-size heap buffer, then copies variable-length data from the frame without enforcing the destination boundary. Refer to the Microsoft Security Update Guide for vendor-supplied technical context.
Attack Vector
The attacker sends malformed LLTD frames to a target Windows Server 2008 host on the same local network. The victim must interact with the topology discovery process, for example by opening the Network Map view. Once triggered, the overflow corrupts heap structures used by the LLTD service and can enable arbitrary code execution in the service context. No verified public proof-of-concept code is available for this issue.
Detection Methods for CVE-2024-30075
Indicators of Compromise
- Unexpected LLTD (EtherType 0x88D9) traffic originating from non-infrastructure hosts on the local segment.
- Crashes or restarts of the lltdsvc service on Windows Server 2008 systems.
- Abnormal child processes spawned by svchost.exe instances hosting lltdsvc.
- Heap corruption events logged in Windows Error Reporting referencing lltdio.sys or lltdsvc.dll.
Detection Strategies
- Deploy network monitoring rules that flag high volumes of LLTD frames or malformed topology discovery messages on VLANs containing legacy Windows Server hosts.
- Enable Windows Event Log forwarding for service crash events (Event ID 7031, 7034) associated with the LLTD service.
- Baseline expected LLTD traffic and alert on deviations, since most modern networks do not require active use of the protocol.
Monitoring Recommendations
- Forward endpoint telemetry from legacy Windows Server 2008 hosts to a centralized SIEM for correlation with network events.
- Monitor for post-exploitation behaviors such as credential access, lateral movement, and persistence attempts originating from the LLTD service context.
- Track patch state of all Windows Server 2008 systems and alert when unpatched hosts appear on production segments.
How to Mitigate CVE-2024-30075
Immediate Actions Required
- Apply the June 2024 Microsoft security update for Windows Server 2008 as documented in the Microsoft Security Update Guide.
- Inventory all Windows Server 2008 SP2 and R2 SP1 hosts and prioritize patching for systems on shared or user-accessible network segments.
- Restrict adjacent-network access to legacy servers through VLAN segmentation and Layer 2 access controls.
Patch Information
Microsoft released a security update on June 11, 2024 that addresses the heap-based buffer overflow in the LLTD components. Note that Windows Server 2008 is outside standard support; patches may only be available through Extended Security Updates (ESU) programs. Consult the Microsoft Security Update Guide for the specific KB article applicable to each affected build.
Workarounds
- Disable the Link-Layer Topology Discovery Mapper I/O Driver (lltdio) and Responder (rspndr) components on hosts that do not require network topology mapping.
- Block EtherType 0x88D9 traffic at network access layer switches where LLTD is not required.
- Isolate Windows Server 2008 hosts on dedicated management VLANs with strict host-based firewall rules.
# Disable LLTD components on Windows Server 2008 using PowerShell
Disable-NetAdapterBinding -Name "*" -ComponentID ms_lltdio
Disable-NetAdapterBinding -Name "*" -ComponentID ms_rspndr
# Verify the components are disabled
Get-NetAdapterBinding -ComponentID ms_lltdio,ms_rspndr
Disclaimer: This content was generated using AI. While we strive for accuracy, please verify critical information with official sources.
