In our first part of the WTF Windows!?!?! Query of the Week, we are going to jump into a fun hunt. Long story short, we had some system applications that were hanging, Windows has an event for this 1002. Great, lets go see why they were hanging!
<Event xmlns='http://schemas.microsoft.com/win/2004/08/events/event'><System><Provider Name='Application Hang'/><EventID Qualifiers='0'>1002</EventID><Level>2</Level><Task>101</Task><Keywords>0x80000000000000</Keywords><TimeCreated SystemTime='2021-05-07T17:03:37.913165700Z'/><EventRecordID>1344</EventRecordID><Channel>Application</Channel><Computer>ad.traetox.net</Computer><Security/></System><EventData><Data>iexplore.exe</Data><Data>11.0.17763.592</Data><Data>8a0</Data><Data>01d74362b99895fa</Data><Data>60000</Data><Data>C:\Program Files (x86)\Internet Explorer\iexplore.exe</Data><Data>0df1f355-f43a-43d3-8205-07df810b6a76</Data><Data></Data><Data></Data><Data>Unknown</Data><Binary>55006E006B006E006F0077006E0000000000</Binary></EventData></Event>
Ok, we have an application, some unstructured execution parameters, version strings, some opaque hex numbers. Cool cool... OOOOH Binary. Clearly that is where all the secrets lie! Lets decode it!
tag=windows winlog Computer Provider=="Application Hang" EventID==1002 Binary EventData
| regex -e EventData "<Data>(?P<exe>[^<]+)</Data>"
| hexlify -d Binary
| table TIMESTAMP Computer exe Binary
Soo... 55006E006B006E006F0077006E0000000000 decodes to "Unknown" in UTF-16. Thanks... And double thanks for the multiple NULL characters at the end.
Next week we'll look at removable storage events; you know, the things that make your air gap NOT an airgap!
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