CodePage Modification Via MODE.COM To Russian Language
Detects a CodePage modification using the "mode.com" utility to Russian language. This behavior has been used by threat actors behind Dharma ransomware.
Sigma rule (View on GitHub)
1title: CodePage Modification Via MODE.COM To Russian Language
2id: 12fbff88-16b5-4b42-9754-cd001a789fb3
3related:
4 - id: d48c5ffa-3b02-4c0f-9a9e-3c275650dd0e
5 type: derived
6status: experimental
7description: |
8 Detects a CodePage modification using the "mode.com" utility to Russian language.
9 This behavior has been used by threat actors behind Dharma ransomware.
10references:
11 - https://learn.microsoft.com/en-us/windows/win32/intl/code-page-identifiers
12 - https://learn.microsoft.com/en-us/windows-server/administration/windows-commands/mode
13 - https://strontic.github.io/xcyclopedia/library/mode.com-59D1ED51ACB8C3D50F1306FD75F20E99.html
14 - https://www.virustotal.com/gui/file/5e75ef02517afd6e8ba6462b19217dc4a5a574abb33d10eb0f2bab49d8d48c22/behavior
15author: Joseliyo Sanchez, @Joseliyo_Jstnk
16date: 2024-01-17
17tags:
18 - attack.defense-evasion
19 - attack.t1036
20logsource:
21 category: process_creation
22 product: windows
23detection:
24 # VT Query: behavior:"mode con cp select=1251"
25 # VT Query: behavior:"mode con cp select=866"
26 selection_img:
27 - Image|endswith: '\mode.com'
28 - OriginalFileName: 'MODE.COM'
29 selection_cli:
30 CommandLine|contains|all:
31 - ' con '
32 - ' cp '
33 - ' select='
34 CommandLine|endswith:
35 - '=1251' # ANSI Cyrillic; Cyrillic (Windows) - Observed ITW by Dharma ransomware
36 - '=866' # OEM Russian; Cyrillic (DOS) - Observed ITW by other malware
37 condition: all of selection_*
38falsepositives:
39 - Russian speaking people changing the CodePage
40level: medium
References
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