Linux Buffer overflow

Rule ID

PH_Rule_TH_Linux_35

Default Status

Enabled

Description

Detects buffer overflow in linux syslog

Severity

MITRE ATT&CK® Tactics

Privilege Escalation

Privilege Escalation consists of techniques that adversaries use to gain higher-level permissions on a system or network. Adversaries can often enter and explore a network with unprivileged access but require elevated permissions to follow through on their objectives. Common approaches are to take advantage of system weaknesses, misconfigurations, and vulnerabilities.

https://attack.mitre.org/tactics/TA0004

MITRE ATT&CK® Techniques

T1547.009

Boot or Logon Autostart Execution: Shortcut Modification

Adversaries may create or edit shortcuts to run a program during system boot or user login. Shortcuts or symbolic links are ways of referencing other files or programs that will be opened or executed when the shortcut is clicked or executed by a system startup process.

https://attack.mitre.org/techniques/T1547/009

Impacts

Server

Data Source

Linux via Syslog

Detection

Correlation

Remediation Guidance

No remediation guidance specified

Time Window

If the following pattern or patterns match an ingested event within the given time window in seconds, trigger an incident.

300 seconds

Trigger Conditions

If the following defined pattern/s occur within a 300 second time window.

Download

SubPattern Definitions

SubPattern Name: Download

This is the named definition of the event query, this is important if multiple subpatterns are defined to distinguish them.

SubPattern Query

This is the query logic that matches incoming events

eventType CONTAIN "Generic_Unix_" AND
          (rawEventMsg CONTAIN "attempt to execute code on stack by" OR
          rawEventMsg REGEXP ".*FTP LOGIN FROM .* 0bin0sh" OR
          rawEventMsg REGEXP ".*rpc.statd\[\d+\]: gethostbyname error for" OR
          rawEventMsg CONTAIN "AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA") AND phEventCategory = 0

Group by Attributes

This defines how matching events are aggregated, only events with the same matching attribute values are grouped into one unique incident ID

reptDevName

Aggregate Constraint

This is most typically a numerical constraint that defines when the rule should trigger an incident

COUNT(*) >= 1

Incident Attribute Mapping

This section defines which fields in matching raw events should be mapped to the incident attributes in the resulting incident.

The available raw event attributes to map are limited to the group by attributes and the aggregate event constraint fields for each subpattern

 hostName = Download.reptDevName

FortiSIEM Rules