Wietze

@wietzebeukema.nl

Threat Detection & Response. Interested in cyber security, tech and politics. Views are my own, unless retweeted.

🆕 Recent additions to LOLBAS-Project.github.io: • sigverif/odbcad32.exe for UAC bypass via GUI • IntelliTrace/dxcap/logger.exe for proxy execution • cmstp.exe for loading arbitrary DLLs • cipher.exe for impairing defences ⭐ Nearly 8,500 GitHub stars - thank you all!

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🔥 macOS cmd-obfuscation with ArgFuscator New: over 60 os-native macOS binaries' command lines can now be obfuscated using #ArgFuscator, bypassing command-line based detections, such as this EDR trying to prevent credential dumping. 👉 Check it out: argfuscator.net

Yet another LNK spoofing flaw: executes any DLL, including remote via WebDAV. Even worse, without Feb 2026 updates, MotW will be ignored. Next to updating, your best defence is to look for RunDLL32+Shell32+Control_RunDLL with non-standard targets. See how this works on github.com/wietze/lnk-i...

#HuntingTipOfTheDay: you know how to spot/decode Base64 or XOR in PowerShell… but what about SecureString? This AES-based encryption is native to PowerShell; attackers have been seen to use this for PowerShell obfuscation. 🔍 Hunt for known SecureString decoding commands

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#HuntingTipOfTheDay: Stuck in vi/vim? Open a reverse shell to exit remotely 🙃 Not just a joke - you can make vi/vim run arbitrary commands, not all methods to do so are well detected. 🔍 Hunt for child processes of vi(m), especially those that are rare in your environment.

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#HuntingTipOfTheDay: AppleScript via osascript is still a popular way for infostealers to get credentials/escalate access. Although some (poorly coded) updaters use this ""legitimately"", hunting for osascript referencing password dialogs might surface behaviour of interest.

#HuntingTipOfTheDay: USB worms are still a thing - often the initial infection happens when a user clicks a malicious shortcut on a USB device. See if you can correlate executions with .LNK files on remote drives to find possible badness.

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#HuntingTipOfTheDay: Florian is right. 🌩️ Cloud creds often linger in Environment Variables, especially on servers/dev machines 🟠 One compromised endpoint could thus lead to a full cloud breach 🔍 Hunt for exposed tokens - if you can see it, so could an attacker (well, kinda)

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#HuntingTipOfTheDay: TCC on macOS can be bypassed by triggering Electron apps' Node.js interface to run arbitrary commands ⚡ By using a Launch Daemon, you can leverage all the app's TCC permissions 🔍 Hunt for processes with ELECTRON_RUN_AS_NODE env var and unusual command lines

#HuntingTipOfTheDay: folders with trailing spaces can be created on Windows, and they cause trouble: 🔴 Hard to delete/rename 🟠 Can hide (malicious) content when the same folder without trailing space exists 🟡 May enable UAC bypass (see next msg) 🔍 Hunt for paths with trailing spaces - highly sus

#HuntingTipOfTheDay: you’ll know that in Linux, files with a leading dot are hidden by default. Attackers may use this to hide payloads or frustrate forensics. Although sometimes used legitimately, you may find unexpected entries when looking for EXECUTIONS of hidden files.

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#HuntingTipOfTheDay: Services can provide persistence. Looking for changes to their commands is common, but the lesser known Environment setting is often overlooked. It could result in stealthy DLL hijacking. Inspect any paths referenced for suspicious files.

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#HuntingTipOfTheDay: explorer.exe /root,"c:/your/executable.exe" will spawn your exe from the main explorer.exe, not a new one. This breaks normal process chains. Hunt for explorer.exe with "/root", as well as explorer spawning unusual children (e.g. rundll32, mshta, powershell).

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#HuntingTipOfTheDay: a common way to execute malicious code on Linux is to download a script via curl/wget and pipe the result into a shell process like bash. Hunt for curl/wget executions followed by an interactive shell within seconds, both having the same parent process.

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#HuntingTipOfTheDay: You have probably heard of .bash_profile and .zshrc, but are you familiar with PowerShell's version of it? Attackers might use this for persistence; monitor modifications of profiles by unexpected processes, and analyse existing files for anomalies.

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#ThreatHuntingTipOfTheDay: Malicious DMGs/PKGs are currently the most popular way for macOS infostealers to get foothold. Use macOS’s kMDItemWhereFroms extended attribute to see origins of downloaded DMG/PKGs; investigate ones that are rare across your IT estate.

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