Welcome to blue tangle

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I've purchased the domain bluetangle.dev and renamed this blog. I really like the imagery of a blue fishing net undergoing constant repair, thinking about the blue team and how hard we struggle to stop things slipping by us. In terms of content, I'll still be poking around at red team and hacker tools and thinking about detections and threat hunts as I go. Here is some DALL-E art to commemorate the change.
Back to regular updates soon.

Popular posts from this blog

Fastening the Seatbelt on.. Threat Hunting for Seatbelt

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  Quick blog entry on detections for the Ghostpack discovery/reconnaissance tool Seatbelt . This entry will focus on looking at command line parameters that can be caught even if the executable itself is renamed, if I have time we can delve into other event log artefacts another time. From the Seatbelt github repo: Seatbelt is a C# project that performs a number of security oriented host-survey "safety checks" relevant from both offensive and defensive security perspectives. So essentially what the tool does is retrieve local system information that might have security or safety implications. In terms of commands that can be tacked on to Seatbelt there are a literal ton of options. But what we are going to focus on here are the command groups, which break the many, many available commands down into categories, so we have: All, User, System, Slack, Chromium, Remote, Misc. The groups above are invoked like this, if you wanted to run all checks: Seatbelt.exe -group=all And so
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Capturing Pcap driver installations

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Today we're looking at Network Sniffing , ATT&CK technique T1040. This is very much a signature based rule but if you are ingesting WinEventlog:Security (and of course you are, right?) and specifically EventCode 4697 ("A service was installed in the system") then you can take the barebones splunk SPL from below and make it work for you. So how are we going to detect network sniffing on Windows endpoints? The installation of the drivers for the various Pcap variants. index=win10 sourcetype="wineventlog:security" EventCode=4697 AND Service_File_Name IN ("*pcap*", "*npcap*", "*npf*", "*nm3*", "*ndiscap*", "*nmnt*", "*windivert*", "*USBPcap*", "*pktmon*") | table _time Account_Name Computer_Name Originating_Computer Service_Name Service_File_Name   The Service_File_Name list is derived from looking at the names of .sys files associated with the most popular packet capture o
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Microsoft Defender, Find User Ignored Threats With Splunk

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  Today we're looking at "vanilla" Microsoft Defender and some SPL to find "severe" or "high" categories of detected threat severity that have subsequently been "ignored" by a user. EventID 1117 gives us our detection, categorization and severity of the threat found and EventID 5007 gives us a log of user changes made, including ignored threats. EventID 5007 logs changes enacted by users to how threats are handled with a field called "New_value", it will look something like this: New value: HKLM\SOFTWARE\Microsoft\Windows Defender\Threats\ThreatIDDefaultAction\2147742972 = 0x6 It is a registry value, the string of numbers at the end is the same ID assigned recorded in EventID 1117, the "0x6" at the end signifies that this is an ignored threat. A little bit of regex retrieves our 5007 newly created "ThreatID" field and we can then compare this to our 1117 ID value to see if they match. We achieve this without reco
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