// question

On Windows, review recent registry changes to detect when the MSC file association was hijacked by a reg add operation. What executable file was configured as the default command under HKCU\Software\Classes\mscfile\shell\open\command?

Reference KQL answer and model-by-model comparison.

02124c37-767e-4b76-9383-c9fc366d9d4c
question id
1/23
models correct
1
valid answer
4%
success rate
// reference answer

Human-validated correct answer for this question.

calc.exe
// model comparison
ModelAnswerKQL queryStatusTriesTimeCost
gemini-2.5-flash-preview-04-17
no answer
no query generatedfail50.00s0.0303
gpt-35-turbo
no answer
no query generatedfail50.00s0.0116
gpt-4-turbo-2024-04-09
no answer
no query generatedfail50.00s0.2355
gpt-4.1
c:\windows\System32\calc.exe
DeviceRegistryEvents
| where tolower(RegistryKey) has "mscfile\\shell\\open\\command"
| where (tolower(RegistryKey) startswith "hkey_current_user" or tolower(RegistryKey) startswith "hkcu")
| where ActionType =~ "RegistryValueSet"
| project TimeGenerated, DeviceName, InitiatingProcessAccountName, InitiatingProcessFileName, InitiatingProcessCommandLine, RegistryKey, RegistryValueName, RegistryValueData
| order by TimeGenerated desc
pass312.97s0.0271
gpt-4.1-finetuned
no answer
no query generatedfail50.00s0.1119
gpt-4.1-mini
no answer
no query generatedfail50.00s0.0064
gpt-4.1-nano
no answer
no query generatedfail50.00s0.0015
gpt-4o
no answer
no query generatedfail50.00s0.0537
gpt-5-high
no answer
no query generatedfail50.00s0.2476
gpt-5-mini-high
no answer
no query generatedfail50.00s0.0168
gpt-5-mini-low
no answer
no query generatedfail50.00s0.0138
gpt-5-mini-medium
no answer
no query generatedfail50.00s0.0204
gpt-5-nano-high
no answer
no query generatedfail50.00s0.0108
gpt-5-nano-medium
no answer
no query generatedfail50.00s0.0127
grok-3-beta
no answer
no query generatedfail50.00s0.0881
grok-3-mini-beta
no answer
no query generatedfail50.00s0.0075
o1-high
no answer
no query generatedfail50.00s0.6550
o1-low
no answer
no query generatedfail50.00s0.8208
o3-high
no answer
no query generatedfail50.00s0.1086
o3-mini-high
no answer
no query generatedfail50.00s0.0419
o3-mini-low
no answer
no query generatedfail50.00s0.0449
o4-mini-high
no answer
no query generatedfail50.00s0.0431
o4-mini-low
no answer
no query generatedfail50.00s0.0492