Suspicious Space Characters in TypedPaths Registry Path - FileFix

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

Detects the occurrence of numerous space characters in TypedPaths registry paths, which may indicate execution via phishing lures using file-fix techniques to hide malicious commands.

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1204.004` User Execution: Malicious Copy and Paste
Defense Evasion	`T1027.010` Obfuscated Files or Information: Command Obfuscation

Event coverage

Provider	Event ID	Title
Sysmon	13	RegistryEvent (Value Set)

Stages and Predicates

Stage 1: `all of selection_key`

Details|contains: '#'
TargetObject|endswith: '\Software\Microsoft\Windows\CurrentVersion\Explorer\TypedPaths\url1'

Stage 2: `all of selection_space_variation`

or:
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '
Details|contains: '            '

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
`Details`	match	corpus 2 (sigma 2) `#` corpus 3 (sigma 3) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2) corpus 2 (sigma 2)
`TargetObject`	ends_with	`\Software\Microsoft\Windows\CurrentVersion\Explorer\TypedPaths\url1` corpus 2 (sigma 2)

Neighbors

Stricter alternatives (narrower than this rule)

The rules below may be useful if you find the current rule is too noisy / lacks specificity.

FileFix - Command Evidence in TypedPaths [sigma] (adds 1 filter) (first-stage match only; downstream stages may differ)