Potential Persistence Via Shim Database In Uncommon Location

Hunt Hypothesis

Detects the installation of a new shim database where the file is located in a non-default location

Detection Rule

Sigma (Original)

title: Potential Persistence Via Shim Database In Uncommon Location
id: 6b6976a3-b0e6-4723-ac24-ae38a737af41
status: test
description: Detects the installation of a new shim database where the file is located in a non-default location
references:
    - https://www.fireeye.com/blog/threat-research/2017/05/fin7-shim-databases-persistence.html
    - https://andreafortuna.org/2018/11/12/process-injection-and-persistence-using-application-shimming/
    - https://www.blackhat.com/docs/asia-14/materials/Erickson/Asia-14-Erickson-Persist-It-Using-And-Abusing-Microsofts-Fix-It-Patches.pdf
author: Nasreddine Bencherchali (Nextron Systems)
date: 2023-08-01
modified: 2023-08-17
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1546.011
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|contains|all:
            - '\SOFTWARE\Microsoft\Windows NT\CurrentVersion\AppCompatFlags\InstalledSDB\'
            - '\DatabasePath'
    filter_main_known_locations:
        Details|contains: ':\Windows\AppPatch\Custom'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Unknown
level: high

KQL (Azure Sentinel)

imRegistry
| where (RegistryKey endswith "\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\AppCompatFlags\\InstalledSDB*" and RegistryKey contains "\\DatabasePath") and (not(RegistryValueData contains ":\\Windows\\AppPatch\\Custom"))

KQL (Microsoft 365 Defender)

DeviceRegistryEvents
| where (RegistryKey endswith "\\SOFTWARE\\Microsoft\\Windows NT\\CurrentVersion\\AppCompatFlags\\InstalledSDB*" and RegistryKey contains "\\DatabasePath") and (not(RegistryValueData contains ":\\Windows\\AppPatch\\Custom"))

Required Data Sources

False Positive Guidance

• Unknown

MITRE ATT&CK Context

• Tactic: Privilege Escalation
• Tactic: Persistence
• Technique: T1546.011 — T1546.011

References

• https://www.fireeye.com/blog/threat-research/2017/05/fin7-shim-databases-persistence.html
• https://andreafortuna.org/2018/11/12/process-injection-and-persistence-using-application-shimming/
• https://www.blackhat.com/docs/asia-14/materials/Erickson/Asia-14-Erickson-Persist-It-Using-And-Abusing-Microsofts-Fix-It-Patches.pdf
• SigmaHQ Rule