CVE-2026-39929: Lakeside SysTrack Agent Out-of-Bounds Read Denial of Service

Technical summary

CVE-2026-39929 is an out-of-bounds read vulnerability in the Command ID 30 UDP packet handler of Lakeside SysTrack Agent. The flaw exists because the application fails to properly validate the bounds of memory access when processing specially crafted UDP packets. Specifically, attackers can craft a UDP payload with an invalid memory address reference at offset 0x4 that triggers an access violation when dereferenced. This causes an unhandled exception and immediate process termination. The vulnerability is classified under CWE-125 (Out-of-bounds Read) and CWE-754 (Improper Check for Unusual or Exceptional Conditions), indicating insufficient input validation and error handling in the packet processing routine.

Business impact

SysTrack Agent is commonly deployed as part of endpoint management and user experience monitoring across enterprise environments. A successful attack causes the agent to crash, interrupting monitoring, telemetry collection, and any dependent workflows. If SysTrack data feeds critical alerting, compliance reporting, or user support tools, an outage could obscure security incidents, delay incident response, and create compliance reporting gaps. Organizations with large deployments face the prospect of coordinated denial of service affecting many endpoints simultaneously if the attack is networked or distributed.

Affected systems

Lakeside SysTrack Agent versions 11.2.1.28 and earlier, 11.3.0.38 and earlier, 11.4.0.24 and earlier, and 11.5.0.15 and earlier are vulnerable. Organizations should verify their deployed versions against the patch guidance provided by Lakeside Software to determine exposure.

Exploitability

Exploitability is high. The attack requires only network access and the ability to send a UDP packet to the agent; no authentication, special privileges, or user interaction are needed. The network vector and low complexity mean an attacker can trigger the crash from any network position if the UDP port is reachable. However, the attack is limited to denial of service and does not allow code execution or data theft, which constrains the overall risk.

Remediation

Upgrade SysTrack Agent to patched versions: 11.2.1.28 or later, 11.3.0.38 or later, 11.4.0.24 or later, or 11.5.0.15 or later, depending on the version branch in use. Verify the exact version requirements with Lakeside Software's official advisory. If immediate patching is not possible, consider restricting UDP access to the SysTrack agent from untrusted network segments using firewall rules or network segmentation.

Patch guidance

Consult Lakeside Software's official security advisory for exact version numbers and deployment instructions. The patch versions referenced in the CVE description should be verified against the vendor's release notes. Organizations should test patches in a non-production environment before rolling out to the full estate, particularly if SysTrack telemetry is used for critical monitoring or compliance.

Detection guidance

Monitor for unexpected crashes or restarts of SysTrack Agent processes on endpoints. Check agent logs for access violation exceptions or unhandled exceptions originating from the UDP packet handler. Network-based detection is challenging without application-level visibility, but organizations with UDP traffic inspection or packet logging capabilities should look for malformed UDP packets sent to the SysTrack agent port with unusual payload structures at offset 0x4. Endpoint detection and response (EDR) tools should flag repeated process crashes of the SysTrack agent executable.

Why prioritize this

Although this vulnerability does not permit code execution and does not affect confidentiality or integrity, the ease of exploitation (network, unauthenticated, low complexity) and the guaranteed denial of service outcome make it a high-priority patch. Organizations heavily dependent on SysTrack for operations and compliance should prioritize this patch to maintain visibility and avoid service disruption.

Risk score, explained

The CVSS 3.1 score of 7.5 (HIGH) reflects a network-accessible, unauthenticated attack with no user interaction required, resulting in complete availability loss for the affected service. The lack of confidentiality or integrity impact prevents a critical rating, but the ease of trigger and broad applicability in enterprise deployments justify the HIGH severity designation.

Frequently asked questions