HackTool - WSASS Execution

Severity: high
Author: Swachchhanda Shrawan Poudel (Nextron Systems)
Source: upstream

Detects execution of WSASS, a tool used to dump LSASS memory on Windows systems by leveraging WER's (Windows Error Reporting) WerFaultSecure.EXE to bypass PPL (Protected Process Light) protections.

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1003.001` OS Credential Dumping: LSASS Memory

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `1 of selection_img`

Image|endswith: '\wsass.exe'

Stage 2: `1 of selection_hash`

Hashes|contains: 'IMPHASH=32F5095C9BBDCACF28FD4060EB4DFC42'

Stage 3: `1 of selection_cli`

CommandLine|re: '(?i)\.exe[\"\'']?\s+[^\"]{0,64}werfaultsecure\.exe[\"\'']?\s+\d{2,10}'

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`	regex_match	`(?i)\.exe[\"\']?\s+[^\"]{0,64}werfaultsecure\.exe[\"\']?\s+\d{2,10}`
`Hashes`	match	`IMPHASH=32F5095C9BBDCACF28FD4060EB4DFC42`
`Image`	ends_with	`\wsass.exe`