Rule Category

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

Alert Message

SERVER-OTHER NTP decodenetnum assertion failure denial of service attempt

Rule Explanation

The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (assertion failure) via a 6 or mode 7 packet containing a long data value. Impact: CVSS base score 6.5 CVSS impact score 3.6 CVSS exploitability score 2.8 confidentialityImpact NONE integrityImpact NONE availabilityImpact NONE Details: Ease of Attack:

What To Look For

Known Usage

No public information

False Positives

No known false positives

Contributors

Talos research team. This document was generated from data supplied by the national vulnerability database, a product of the national institute of standards and technology. For more information see [nvd].

MITRE ATT&CK Framework

Tactic:

Technique:

For reference, see the MITRE ATT&CK vulnerability types here: https://attack.mitre.org

CVE

Additional Links

Rule Vulnerability

CVE Additional Information

CVE-2015-7855
The decodenetnum function in ntpd in NTP 4.2.x before 4.2.8p4, and 4.3.x before 4.3.77 allows remote attackers to cause a denial of service (assertion failure) via a 6 or mode 7 packet containing a long data value.
Details
Severity Base Score6.5
Impact Score3.6 Exploit Score2.8
Confidentiality ImpactNONE Integrity ImpactNONE
Availability ImpactHIGH Access Vector
Authentication Ease of Access