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Trust Me, I’m a Shortcut

Windows’ primary mechanism for shortcuts, LNK files, is frequently abused by threat actors for payload delivery and persistence. This blog post introduces several new LNK file flaws that, amongst other things, allow attackers to fully spoof an LNK’s target. It also introduces lnk-it-up, a tool suite that can generate such deceptive LNK files, as well as detect anomalous ones.

Bypassing Detections with Command-Line Obfuscation

Defensive tools like AVs and EDRs rely on command-line arguments for detecting malicious activity. This post demonstrates how command-line obfuscation, a shell-independent technique that exploits executables’ parsing “flaws”, can bypass such detections. It also introduces ArgFuscator, a new tool that documents obfuscation opportunities and generates obfuscated command lines.

Why bother with argv[0]?

The first argument of a program’s command line, typically reflecting the program’s name/path and often referred to as argv[0], can in most cases be set to an arbitrary value without affecting the process’ flow. Making the case against argv[0], this post demonstrates how it can be used to deceive security analysts, bypass detections and break defensive software, across all main operating systems.

Save the Environment (Variable)

By manipulating environment variables on process level, it is possible to let trusted applications load arbitrary DLLs and execute malicious code. This post lists nearly 100 executables vulnerable to this type of DLL Hijacking on Windows 11 (21H2); it is demonstrated how this can achieved with just three lines of VBScript.

Windows Command-Line Obfuscation

Many Windows applications have multiple ways in which the same command line can be expressed, usually for compatibility or ease-of-use reasons. As a result, command-line arguments are implemented inconsistently making detecting specific commands harder due to the number of variations. This post shows how more than 40 often-used, built-in Windows applications are vulnerable to forms of command-line…

Hijacking DLLs in Windows

DLL Hijacking is a popular technique for executing malicious payloads. This post lists nearly 300 executables vulnerable to relative path DLL Hijacking on Windows 10 (1909), and shows how with a few lines of VBScript some of the DLL hijacks can be executed with elevated privileges, bypassing UAC.

PowerShell Obfuscation using SecureString

PowerShell has built-in functionality to save sensitive plaintext data to an encrypted object called SecureString. Malicious actors have exploited this functionality as a means to obfuscate PowerShell commands. This blog post discusses SecureString, examples seen in the wild, and presents a tool [8] that helps analyse SecureString obfuscated commands.

Spoofing Google Search results

By adding two parameters to any Google Search URL, you can replace search results with a Knowledge Graph card of your choice. A malicious user can use this to generate false information or ‘fake news’.