Potential Privilege Escalation Using Symlink Between Osk and Cmd

 1title: Potential Privilege Escalation Using Symlink Between Osk and Cmd
 2id: e9b61244-893f-427c-b287-3e708f321c6b
 3status: test
 4description: Detects the creation of a symbolic link between "cmd.exe" and the accessibility on-screen keyboard binary (osk.exe) using "mklink". This technique provides an elevated command prompt to the user from the login screen without the need to log in.
 5references:
 6    - https://github.com/redcanaryco/atomic-red-team/blob/5c1e6f1b4fafd01c8d1ece85f510160fc1275fbf/atomics/T1546.008/T1546.008.md
 7    - https://ss64.com/nt/mklink.html
 8author: frack113
 9date: 2022-12-11
10modified: 2022-12-20
11tags:
12    - attack.privilege-escalation
13    - attack.persistence
14    - attack.t1546.008
15logsource:
16    product: windows
17    category: process_creation
18detection:
19    selection_img:
20        - Image|endswith: '\cmd.exe'
21        - OriginalFileName: 'Cmd.Exe'
22    selection_cli:
23        CommandLine|contains|all:
24            - 'mklink'
25            - '\osk.exe'
26            - '\cmd.exe'
27    condition: all of selection_*
28falsepositives:
29    - Unknown
30level: high

References

• atomic-red-team/atomics/T1546.008/T1546.008.md at 5c1e6f1b4fafd01c8d1ece85f510160fc1275fbf · redcanaryco/atomic-red-team

  

  Small and highly portable detection tests based on MITRE's ATT&CK. - redcanaryco/atomic-red-team

  
  Read More

• MKLink - Windows CMD - SS64.com

  MKLink Create a symbolic link to a directory or a file, or create a hard file link or directory junction. Syntax MKLINK [[/D] | [/H] | [/J]] LinkName Target Key: /D Create a Directory symbolic link...

  
  Read More

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