Potential SMB Relay Attack Tool Execution

Status: test
Severity: critical
Log source: category process_creation, product windows
Author: Florian Roth (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects different hacktools used for relay attacks on Windows for privilege escalation

Known false positives

Legitimate files with these rare hacktool names

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1557.001` Adversary-in-the-Middle: Name Resolution Poisoning and SMB Relay
Collection	`T1557.001` Adversary-in-the-Middle: Name Resolution Poisoning and SMB Relay

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation
Security-Auditing	Event ID 4688: A new process has been created.

Rule body

title: Potential SMB Relay Attack Tool Execution
id: 5589ab4f-a767-433c-961d-c91f3f704db1
status: test
description: Detects different hacktools used for relay attacks on Windows for privilege escalation
references:
    - https://foxglovesecurity.com/2016/09/26/rotten-potato-privilege-escalation-from-service-accounts-to-system/
    - https://pentestlab.blog/2017/04/13/hot-potato/
    - https://github.com/ohpe/juicy-potato
    - https://hunter2.gitbook.io/darthsidious/other/war-stories/domain-admin-in-30-minutes
    - https://hunter2.gitbook.io/darthsidious/execution/responder-with-ntlm-relay-and-empire
    - https://www.localpotato.com/
author: Florian Roth (Nextron Systems)
date: 2021-07-24
modified: 2023-02-14
tags:
    - attack.collection
    - attack.execution
    - attack.credential-access
    - attack.t1557.001
logsource:
    category: process_creation
    product: windows
detection:
    selection_pe:
        Image|contains:
            - 'PetitPotam'
            - 'RottenPotato'
            - 'HotPotato'
            - 'JuicyPotato'
            - '\just_dce_'
            - 'Juicy Potato'
            - '\temp\rot.exe'
            - '\Potato.exe'
            - '\SpoolSample.exe'
            - '\Responder.exe'
            - '\smbrelayx'
            - '\ntlmrelayx'
            - '\LocalPotato'
    selection_script:
        CommandLine|contains:
            - 'Invoke-Tater'
            - ' smbrelay'
            - ' ntlmrelay'
            - 'cme smb '
            - ' /ntlm:NTLMhash '
            - 'Invoke-PetitPotam'
            - '.exe -t * -p '  # JuicyPotatoNG pattern https://github.com/antonioCoco/JuicyPotatoNG
    selection_juicypotato_enum:  # appears when JuicyPotatoNG is used with -b
        CommandLine|contains: '.exe -c "{'
        CommandLine|endswith: '}" -z'
    filter_hotpotatoes:  # known goodware https://hotpot.uvic.ca/
        Image|contains:
            - 'HotPotatoes6'
            - 'HotPotatoes7'
            - 'HotPotatoes ' # Covers the following: 'HotPotatoes 6', 'HotPotatoes 7', 'HotPotatoes Help', 'HotPotatoes Tutorial'
    condition: 1 of selection_* and not 1 of filter_*
falsepositives:
    - Legitimate files with these rare hacktool names
level: critical

Stages and Predicates

Stage 0: `condition`

1 of selection_* and not 1 of filter_*

Stage 1: `selection_pe`

selection_pe:
    Image|contains:
        - 'PetitPotam'
        - 'RottenPotato'
        - 'HotPotato'
        - 'JuicyPotato'
        - '\just_dce_'
        - 'Juicy Potato'
        - '\temp\rot.exe'
        - '\Potato.exe'
        - '\SpoolSample.exe'
        - '\Responder.exe'
        - '\smbrelayx'
        - '\ntlmrelayx'
        - '\LocalPotato'

Stage 2: `selection_script`

selection_script:
    CommandLine|contains:
        - 'Invoke-Tater'
        - ' smbrelay'
        - ' ntlmrelay'
        - 'cme smb '
        - ' /ntlm:NTLMhash '
        - 'Invoke-PetitPotam'
        - '.exe -t * -p '

Stage 3: `selection_juicypotato_enum`

selection_juicypotato_enum:
    CommandLine|contains: '.exe -c "{'
    CommandLine|endswith: '}" -z'

Stage 4: `not filter_hotpotatoes`

filter_hotpotatoes:
    Image|contains:
        - 'HotPotatoes6'
        - 'HotPotatoes7'
        - 'HotPotatoes '

Exclusions

The rule actively suppresses these predicates.

Field	Kind	Excluded values	Search
`Image`	match	`HotPotatoes`	`excludes:Image` `field:"Image" value:"HotPotatoes "`
`Image`	match	`HotPotatoes6`	`excludes:Image` `field:"Image" value:"HotPotatoes6"`
`Image`	match	`HotPotatoes7`	`excludes:Image` `field:"Image" value:"HotPotatoes7"`

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	ends_with	`}" -z`	`field:"CommandLine" kind:ends_with`
`CommandLine`	match	`/ntlm:NTLMhash` `ntlmrelay` `smbrelay` `.exe -c "{` `.exe -t * -p` `Invoke-PetitPotam` `Invoke-Tater` corpus 2 (sigma 2) `cme smb`	`field:"CommandLine" kind:match`
`Image`	match	`HotPotato` `Juicy Potato` `JuicyPotato` `PetitPotam` `RottenPotato` `\LocalPotato` `\Potato.exe` `\Responder.exe` `\SpoolSample.exe` `\just_dce_` `\ntlmrelayx` corpus 2 (sigma 2) `\smbrelayx` corpus 2 (sigma 2) `\temp\rot.exe`	`field:"Image" kind:match`

Potential SMB Relay Attack Tool Execution

Known false positives

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_pe

Stage 2: selection_script

Stage 3: selection_juicypotato_enum

Stage 4: not filter_hotpotatoes

Exclusions

Indicators

Stage 0: `condition`

Stage 1: `selection_pe`

Stage 2: `selection_script`

Stage 3: `selection_juicypotato_enum`

Stage 4: `not filter_hotpotatoes`