Capture Credentials with Rpcping.exe

Severity: medium
Author: Julia Fomina, oscd.community
Source: upstream

Detects using Rpcping.exe to send a RPC test connection to the target server (-s) and force the NTLM hash to be sent in the process.

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1003` OS Credential Dumping

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_main_img`

or:
Image|endswith: '\RpcPing.exe'
OriginalFileName: '\RpcPing.exe'

Stage 2: `all of selection_main_flag`

CommandLine|contains: -s

Stage 3: `1 of selection_cli_ntlm`

CommandLine|contains: -u
CommandLine|contains: NTLM

Stage 4: `1 of selection_cli_ncacn`

CommandLine|contains: -t
CommandLine|contains: ncacn_np

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.

Field	Kind	Values
`CommandLine`	match	`-s` corpus 2 (sigma 2) `-t` `-u` corpus 3 (sigma 3) `NTLM` `ncacn_np`
`Image`	ends_with	`\RpcPing.exe`
`OriginalFileName`	eq	`\RpcPing.exe`

Capture Credentials with Rpcping.exe

MITRE ATT&CK coverage

Event coverage

Stages and Predicates

Stage 1: all of selection_main_img

Stage 2: all of selection_main_flag

Stage 3: 1 of selection_cli_ntlm

Stage 4: 1 of selection_cli_ncacn

Indicators

Stage 1: `all of selection_main_img`

Stage 2: `all of selection_main_flag`

Stage 3: `1 of selection_cli_ntlm`

Stage 4: `1 of selection_cli_ncacn`