Single Letter Process On Endpoint
The following analytic detects processes with names consisting of a single letter, which is often indicative of malware or an attacker attempting to evade detection. This detection leverages data from Endpoint…
Description
The following analytic detects processes with names consisting of a single letter, which is often indicative of malware or an attacker attempting to evade detection. This detection leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant because attackers use such techniques to obscure their presence and carry out malicious activities like data theft or ransomware attacks. If confirmed malicious, this behavior could lead to unauthorized access, data exfiltration, or system compromise. Immediate investigation is required to determine the legitimacy of the process.
Detection logic
Detection requirements
- Platform
- LinuxmacOSWindows
The rule states no platform. This is derived from the ATT&CK technique it maps to.
- Log source category
- crowdstrike_processrollup2sysmon_eventid_1windows_event_log_security_4688
Known benign triggers
- Single-letter executables are not always malicious. Investigate this activity with your normal incident-response process.
MITRE ATT&CK mappings
0 exclusive techniques.This is coverage no other published rule has; it is not this rule's total technique count.
No references are available for this detection.
From the source
- At source
- Open at source
- Upstream identifier
- a4214f0b-e01c-41bc-8cc4-d2b71e3056b4
- Tagged by the source as
- Compromised Windows HostDHS Report TA18-074AEndpointendpointSplunk CloudSplunk EnterpriseSplunk Enterprise Securityendpoint
Licence
- Published under
- Apache License 2.0Read the licence
- Attribution
- Required
- Obtained under
- Apache-2.0Read the origin licence
Authorship
- Written by
- Published
- Aug 26, 2026
- Version
- 1