Detection rules › Sigma

Dump Credentials from Windows Credential Manager With PowerShell

Status
test
Severity
medium
Log source
product windows, category ps_script
Author
frack113
Source
github.com/SigmaHQ/sigma

Adversaries may search for common password storage locations to obtain user credentials. Passwords are stored in several places on a system, depending on the operating system or application holding the credentials.

MITRE ATT&CK coverage

TacticTechniques
Credential AccessT1555 Credentials from Password Stores

Event coverage

Rule body yaml

title: Dump Credentials from Windows Credential Manager With PowerShell
id: 99c49d9c-34ea-45f7-84a7-4751ae6b2cbc
status: test
description: |
    Adversaries may search for common password storage locations to obtain user credentials.
    Passwords are stored in several places on a system, depending on the operating system or application holding the credentials.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1555/T1555.md
author: frack113
date: 2021-12-20
modified: 2022-12-25
tags:
    - attack.credential-access
    - attack.t1555
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection_kiddie:
        ScriptBlockText|contains:
            - 'Get-PasswordVaultCredentials'
            - 'Get-CredManCreds'
    selection_rename_Password:
        ScriptBlockText|contains|all:
            - 'New-Object'
            - 'Windows.Security.Credentials.PasswordVault'
    selection_rename_credman:
        ScriptBlockText|contains|all:
            - 'New-Object'
            - 'Microsoft.CSharp.CSharpCodeProvider'
            - '[System.Runtime.InteropServices.RuntimeEnvironment]::GetRuntimeDirectory())'
            - 'Collections.ArrayList'
            - 'System.CodeDom.Compiler.CompilerParameters'
    condition: 1 of selection_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: condition

1 of selection_*

Stage 1: selection_kiddie

selection_kiddie:
    ScriptBlockText|contains:
        - 'Get-PasswordVaultCredentials'
        - 'Get-CredManCreds'

Stage 2: selection_rename_Password

selection_rename_Password:
    ScriptBlockText|contains|all:
        - 'New-Object'
        - 'Windows.Security.Credentials.PasswordVault'

Stage 3: selection_rename_credman

selection_rename_credman:
    ScriptBlockText|contains|all:
        - 'New-Object'
        - 'Microsoft.CSharp.CSharpCodeProvider'
        - '[System.Runtime.InteropServices.RuntimeEnvironment]::GetRuntimeDirectory())'
        - 'Collections.ArrayList'
        - 'System.CodeDom.Compiler.CompilerParameters'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
ScriptBlockTextmatch
  • Collections.ArrayList
  • Get-CredManCreds
  • Get-PasswordVaultCredentials
  • Microsoft.CSharp.CSharpCodeProvider
  • New-Object corpus 8 (sigma 7, splunk 1)
  • System.CodeDom.Compiler.CompilerParameters
  • Windows.Security.Credentials.PasswordVault corpus 2 (sigma 2)
  • [System.Runtime.InteropServices.RuntimeEnvironment]::GetRuntimeDirectory())