Potential Defense Evasion Via Right-to-Left Override

 1title: Potential Defense Evasion Via Right-to-Left Override
 2id: ad691d92-15f2-4181-9aa4-723c74f9ddc3
 3status: test
 4description: |
 5    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.
 6    This is used as an obfuscation and masquerading techniques.    
 7references:
 8    - https://redcanary.com/blog/right-to-left-override/
 9    - https://www.malwarebytes.com/blog/news/2014/01/the-rtlo-method
10    - https://unicode-explorer.com/c/202E
11author: Micah Babinski, @micahbabinski
12date: 2023/02/15
13tags:
14    - attack.defense_evasion
15    - attack.t1036.002
16logsource:
17    category: process_creation
18    product: windows
19detection:
20    selection:
21        CommandLine|contains: "\u202e"
22    condition: selection
23falsepositives:
24    - Commandlines that contains scriptures such as arabic or hebrew might make use of this character
25level: high

References

• Right-to-Left Override: Detecting Attacks With EDR Data

  

  Our Security Operations team loves to share insights on TTPs when we see them in the wild. Today an oldie but a goodie: right-to-left override attacks.

  
  Read More

• The RTLO method | Malwarebytes Labs

  

  RTLO can be used to spoof fake extensions. Learn how malware writers are using this old trick to spread malware.

  
  Read More

• U+202E RIGHT-TO-LEFT OVERRIDE - Unicode Explorer

  U+202E RIGHT-TO-LEFT OVERRIDE, copy and paste, unicode character symbol info, commonly abbreviated RLO

  
  Read More

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