Threat Huntlowtest

Access To Chromium Browsers Sensitive Files By Uncommon Applications

Detects file access requests to chromium based browser sensitive files by uncommon processes. Could indicate potential attempt of stealing sensitive information.

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Launch
X__Junior (Nextron Systems)Created Mon Jul 29c5f37810-a85f-4186-81e9-33f23abb4141windows
Hunting Hypothesis
Log Source
Windowsfile_access
ProductWindows← raw: windows
Categoryfile_access← raw: file_access

Definition

Requirements: Microsoft-Windows-Kernel-File ETW provider

Detection Logic
Detection Logic4 selectors
detection:
    selection:
        FileName|contains:
            - '\User Data\Default\Cookies'
            - '\User Data\Default\History'
            - '\User Data\Default\Network\Cookies'
            - '\User Data\Default\Web Data'
    filter_main_system:
        Image: System
    filter_main_generic:
        # This filter is added to avoid large amount of FP with 3rd party software. You should remove this in favour of specific filter per-application
        Image|startswith:
            - 'C:\Program Files (x86)\'
            - 'C:\Program Files\'
            - 'C:\Windows\system32\'
            - 'C:\Windows\SysWOW64\'
    filter_optional_defender:
        Image|startswith: 'C:\ProgramData\Microsoft\Windows Defender\'
        Image|endswith:
            - '\MpCopyAccelerator.exe'
            - '\MsMpEng.exe'
    condition: selection and not 1 of filter_main_* and not 1 of filter_optional_*
False Positives

Antivirus, Anti-Spyware, Anti-Malware Software

Backup software

Legitimate software installed on partitions other than "C:\"

Searching software such as "everything.exe"

References
1
Resolving title…
Internal Research
MITRE ATT&CK

Other

detection.threat-hunting
Rule Metadata
Rule ID
c5f37810-a85f-4186-81e9-33f23abb4141
Status
test
Level
low
Type
Threat Hunt
Created
Mon Jul 29
Path
rules-threat-hunting/windows/file/file_access/file_access_win_browsers_chromium_sensitive_files.yml
Raw Tags
attack.t1003attack.credential-accessdetection.threat-hunting
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