Detection rules › Sigma

Credential Manager Access By Uncommon Applications

Status
test
Severity
medium
Log source
category file_access, product windows
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects suspicious processes based on name and location that access the windows credential manager and vault. Which can be a sign of credential stealing. Example case would be usage of mimikatz "dpapi::cred" function

Known false positives

  • Legitimate software installed by the users for example in the "AppData" directory may access these files (for any reason).

MITRE ATT&CK coverage

TacticTechniques
Credential Access

Rule body

title: Credential Manager Access By Uncommon Applications
id: 407aecb1-e762-4acf-8c7b-d087bcff3bb6
status: test
description: |
    Detects suspicious processes based on name and location that access the windows credential manager and vault.
    Which can be a sign of credential stealing. Example case would be usage of mimikatz "dpapi::cred" function
references:
    - https://hunter2.gitbook.io/darthsidious/privilege-escalation/mimikatz
    - https://www.absolomb.com/2018-01-26-Windows-Privilege-Escalation-Guide/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2022-10-11
modified: 2026-07-28
tags:
    - attack.t1003
    - attack.credential-access
logsource:
    category: file_access
    product: windows
    definition: 'Requirements: Microsoft-Windows-Kernel-File ETW provider'
detection:
    selection:
        FileName|contains:
            - '\AppData\Local\Microsoft\Credentials\'
            - '\AppData\Roaming\Microsoft\Credentials\'
            - '\AppData\Local\Microsoft\Vault\'
            - '\ProgramData\Microsoft\Vault\'
    filter_main_system_folders:
        Image|startswith:
            - 'C:\Program Files\'
            - 'C:\Program Files (x86)\'
            - 'C:\Windows\system32\'
            - 'C:\Windows\SysWOW64\'
    filter_main_explorer:
        Image: 'C:\Windows\explorer.exe'
    condition: selection and not 1 of filter_main_*
falsepositives:
    - Legitimate software installed by the users for example in the "AppData" directory may access these files (for any reason).
# Increase level after false positives filters are good enough
level: medium

Stages and Predicates

Stage 0: condition

selection and not 1 of filter_main_*

Stage 1: selection

selection:
    FileName|contains:
        - '\AppData\Local\Microsoft\Credentials\'
        - '\AppData\Roaming\Microsoft\Credentials\'
        - '\AppData\Local\Microsoft\Vault\'
        - '\ProgramData\Microsoft\Vault\'

Stage 2: not filter_main_*

filter_main_system_folders:
    Image|startswith:
        - 'C:\Program Files\'
        - 'C:\Program Files (x86)\'
        - 'C:\Windows\system32\'
        - 'C:\Windows\SysWOW64\'
filter_main_explorer:
    Image: 'C:\Windows\explorer.exe'

Exclusions

The rule actively suppresses these predicates.

FieldKindExcluded valuesSearch
ImageeqC:\Windows\explorer.exeexcludes:Image field:"Image" value:"C:\Windows\explorer.exe"
Imagestarts_withC:\Program Files (x86)\excludes:Image field:"Image" value:"C:\Program Files (x86)\"
Imagestarts_withC:\Program Files\excludes:Image field:"Image" value:"C:\Program Files\"
Imagestarts_withC:\Windows\SysWOW64\excludes:Image field:"Image" value:"C:\Windows\SysWOW64\"
Imagestarts_withC:\Windows\system32\excludes:Image field:"Image" value:"C:\Windows\system32\"

Indicators

These rows show field, operator, and value matches.

FieldKindValuesSearch
FileNamematch
  • \AppData\Local\Microsoft\Credentials\
  • \AppData\Local\Microsoft\Vault\
  • \AppData\Roaming\Microsoft\Credentials\
  • \ProgramData\Microsoft\Vault\
field:"file_name" kind:match