fix(scanner/windows): allow only cab file scan for offline scan

[MaineK00n]

If this Pull Request is work in progress, Add a prefix of “[WIP]” in the title.

What did you implement:

Even though an offline scan was specified, depending on the ServerSelection, the scanner would still connect to Windows Update or Windows Server Update Services (WSUS) server.
To ensure that this is a strictly offline scan, offline scans do not access Windows Update or WSUS server.

Type of change

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

setup

$ cat << EOS > config.toml
version = "v2"

[default]

[servers]

[server.windows]
host = "127.0.0.1"
port = "2222"
user = "vagrant"
keyPath = "/home/vuls/vuls-targets-docker/.ssh/id_rsa"
scanMode           = ["fast", "offline"]
scanModules        = ["ospkg"]

[servers.windows.windows]
serverSelection = 1
EOS

before

$ vuls scan -debug 2>&1 | grep "UpdateSearcher.search"
time="Jun  9 12:20:30" level=debug msg="Executing... powershell.exe -NoProfile -NonInteractive \"$UpdateSession = (New-Object -ComObject Microsoft.Update.Session); $UpdateSearcher = $UpdateSession.CreateUpdateSearcher(); $UpdateSearcher.ServerSelection = 1; $UpdateSearcher.search(\\\"IsInstalled = 1 and RebootRequired = 0 and Type='Software'\\\").Updates | ForEach-Object -MemberName KBArticleIDs\""
...

after

$ vuls scan -debug 2>&1 | grep "UpdateSearcher.search"
(empty)

Checklist:

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Is this ready for review?: YES

Reference

[shino]

🥂