Add Insecure Download Source To Winget

Severity: high
Author: Nasreddine Bencherchali (Nextron Systems)
Source: upstream

Detects usage of winget to add a new insecure (http) download source. Winget will not allow the addition of insecure sources, hence this could indicate potential suspicious activity (or typos)

MITRE ATT&CK coverage

Tactic	Techniques
Execution	`T1059` Command and Scripting Interpreter

Event coverage

Provider	Event ID	Title
Sysmon	1	Process creation

Stages and Predicates

Stage 1: `all of selection_img`

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

Stage 2: `all of selection_cli`

CommandLine|contains: 'add '
CommandLine|contains: 'http://'
CommandLine|contains: 'source '

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	`add` corpus 9 (sigma 9) `http://` corpus 15 (sigma 15) `source` corpus 3 (sigma 3)
`Image`	ends_with	`\winget.exe` corpus 5 (sigma 5)
`OriginalFileName`	eq	`winget.exe` corpus 4 (sigma 4)