Potential Defense Evasion Via Right-to-Left Override

Severity: high
Author: Micah Babinski, @micahbabinski, Swachchhanda Shrawan Poudel (Nextron Systems), Luc Génaux
Source: upstream

Detects the presence of the "u202+E" character, which causes a terminal, browser, or operating system to render text in a right-to-left sequence. This character is used as an obfuscation and masquerading techniques by adversaries to trick users into opening malicious files.

MITRE ATT&CK coverage

Tactic	Techniques
Defense Evasion	`T1036.002` Masquerading: Right-to-Left Override

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation
Security-Auditing	4688	A new process has been created.

Stages and Predicates

Stage 1: `selection`

or:
CommandLine|contains: '[U+202E]'
CommandLine|contains: '\u202e'
CommandLine|contains: '‮'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.