Rule Category

SERVER-OTHER -- Snort has detected traffic exploiting vulnerabilities in a server in the network.

Alert Message

SERVER-OTHER Network Time Server denial of service attempt

Rule Explanation

This event is generated when an attempt to exploit CVE-2018-7658 is detected. Impact: Attempted Denial of Service Details: Network Time System (Server) "NTSServerSvc" service listens on Port 7001, unauthenticated remote attackers can crash the Server by sending exactly 11 bytes to the target system. Systems which may depend on critical time synchronization could then potentially be impacted. Ease of Attack: Simple, a proof of concept exists in the wild.

What To Look For

Known Usage

No public information

False Positives

No known false positives


Cisco Talos Intelligence Group

MITRE ATT&CK Framework



For reference, see the MITRE ATT&CK vulnerability types here:


Rule Vulnerability

CVE Additional Information

NTSServerSvc.exe in the server in Softros Network Time System 2.3.4 allows remote attackers to cause a denial of service (daemon crash) by sending exactly 11 bytes.
Severity Base Score
Impact Score Exploit Score
Confidentiality Impact Integrity Impact
Availability Impact Access Vector
Authentication Ease of Access