Rule Category

SERVER-WEBAPP -- Snort has detected traffic exploiting vulnerabilities in web based applications on servers.

Alert Message

SERVER-WEBAPP Apache Tomcat HTTP/2 denial of service attempt

Rule Explanation

The rule looks for indication of multiple h2c upgrade attempts are made in succession, indicating a potential attempt to exhaust processor resources.

What To Look For

This rule fires upon attempted exploitation of CVE-2020-13934, a denial of service vulnerability of Apache Tomcat.

Known Usage

No public information

False Positives

No known false positives

Contributors

Cisco Talos Intelligence Group

MITRE ATT&CK Framework

Tactic: Impact

Technique: Endpoint Denial of Service

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

Rule Vulnerability

Denial of Service

Denial of Service attacks aim to make a server or program unresponsive for users. These attacks may be volume-based, to overwhelm the system, or they may use certain logical flaws in the software to cut the service off from the users. The attack may come from one or multiple sources. These attacks do not usually lead to a remote code execution. Volume based attacks are best handled using a firewall application.

CVE Additional Information