CVE-2026-7852: Unrestricted File Upload in Limatek's LimRAD NAC

Synopsis

An unrestricted file upload vulnerability in Limatek System Inc. LimRAD NAC allows an unauthenticated remote attacker to upload and execute arbitrary files on the server. The vulnerability is reachable over the network and requires no credentials or user interaction, as reflected in the CVSS vector (AV:N/AC:L/PR:N/UI:N). Successful exploitation gives the attacker full remote code execution, with high impact across confidentiality, integrity, and availability. A patched-image rebuild at version 5.5.7.3.9 is available on HarborGuard for environments running an affected version.

HarborGuard Coverage

Exploit Conditions

• Network reachabilityRequired

  The vulnerable upload endpoint is exposed over the network, so the attacker must be able to reach the service via a standard network connection.

• AuthenticationNot required

  No credentials of any kind are required; the upload functionality is accessible to unauthenticated requests.

• Victim interactionNot required

  The attacker completes the exploit entirely on their own with no action needed from any user of the system.

• Attack complexityDetail

  Attack complexity is low, meaning the exploit is reliable and does not depend on race conditions, special memory layout, or any other environmental prerequisite.

Blast Radius

• A successful attacker executes arbitrary server-side code by uploading a malicious file and triggering its inclusion, gaining a remote shell on the host.
• The attacker reads all data accessible to the application process, including stored credentials, session tokens, and NAC policy records.
• The attacker modifies or deletes NAC configuration, access control policies, and persisted application data.
• The attacker can crash or otherwise disable the LimRAD NAC service, disrupting network access control enforcement for the affected environment.