COM Object Hijacking Via Modification Of Default System CLSID Default Value

 1title: COM Object Hijacking Via Modification Of Default System CLSID Default Value
 2id: 790317c0-0a36-4a6a-a105-6e576bf99a14
 3related:
 4    - id: 3d968d17-ffa4-4bc0-bfdc-f139de76ce77
 5      type: obsolete
 6    - id: a0ff33d8-79e4-4cef-b4f3-9dc4133ccd12
 7      type: obsolete
 8status: experimental
 9description: Detects potential COM object hijacking via modification of default system CLSID.
10references:
11    - https://www.microsoft.com/security/blog/2022/07/27/untangling-knotweed-european-private-sector-offensive-actor-using-0-day-exploits/ (idea)
12    - https://unit42.paloaltonetworks.com/snipbot-romcom-malware-variant/
13    - https://blog.talosintelligence.com/uat-5647-romcom/
14author: Nasreddine Bencherchali (Nextron Systems)
15date: 2024-07-16
16modified: 2024-10-18
17tags:
18    - attack.persistence
19    - attack.t1546.015
20logsource:
21    category: registry_set
22    product: windows
23detection:
24    selection_target_root:
25        TargetObject|contains: '\CLSID\'
26        TargetObject|endswith:
27            - '\InprocServer32\(Default)'
28            - '\LocalServer32\(Default)'
29    selection_target_builtin_clsid:
30        TargetObject|contains:
31            # Note: Add other legitimate CLSID
32            - '\{1f486a52-3cb1-48fd-8f50-b8dc300d9f9d}\'
33            - '\{2155fee3-2419-4373-b102-6843707eb41f}\'
34            - '\{4590f811-1d3a-11d0-891f-00aa004b2e24}\'
35            - '\{4de225bf-cf59-4cfc-85f7-68b90f185355}\'
36            - '\{ddc05a5a-351a-4e06-8eaf-54ec1bc2dcea}\'
37            - '\{F56F6FDD-AA9D-4618-A949-C1B91AF43B1A}\'
38            - '\{F82B4EF1-93A9-4DDE-8015-F7950A1A6E31}\'
39    selection_susp_location_1:
40        Details|contains:
41            # Note: Add more suspicious paths and locations
42            - ':\Perflogs\'
43            - '\AppData\Local\'
44            - '\Desktop\'
45            - '\Downloads\'
46            - '\Microsoft\Windows\Start Menu\Programs\Startup\'
47            - '\System32\spool\drivers\color\' # as seen in the knotweed blog
48            - '\Temporary Internet'
49            - '\Users\Public\'
50            - '\Windows\Temp\'
51            - '%appdata%'
52            - '%temp%'
53            - '%tmp%'
54    selection_susp_location_2:
55        - Details|contains|all:
56              - ':\Users\'
57              - '\Favorites\'
58        - Details|contains|all:
59              - ':\Users\'
60              - '\Favourites\'
61        - Details|contains|all:
62              - ':\Users\'
63              - '\Contacts\'
64        - Details|contains|all:
65              - ':\Users\'
66              - '\Pictures\'
67    condition: all of selection_target_* and 1 of selection_susp_location_*
68falsepositives:
69    - Unlikely
70level: high