January 17, 2020

CVE-2019-19470: Rumble in the Pipe

This blog post describes an interesting privilege escalation from a local user to SYSTEM for a well-known local firewall solution called TinyWall in versions prior to 2.1.13. Besides a .NET deserialization flaw through Named Pipe communication, an authentication bypass is explained as well.

August 1, 2019

Exploiting H2 Database with native libraries and JNI

Techniques to gain code execution in an H2 Database Engine are already well known but require H2 being able to compile Java code on the fly. This blog post will show a previously undisclosed way of exploiting H2 without the need of the Java compiler being available, a way that leads us through the native world just to return into the Java world using Java Native Interface (JNI).

July 19, 2019

Heap-based AMSI bypass for MS Excel VBA and others


This blog post describes how to bypass Microsoft's AMSI (Antimalware Scan Interface) in Excel using VBA (Visual Basic for Applications). In contrast to other bypasses this approach does not use hardcoded offsets or opcodes but identifies crucial data on the heap and modifies it. The idea of an heap-based bypass has been mentioned by other researchers before but at the time of writing this article no public PoC was available. This blog post will provide the reader with some insights into the AMSI implementation and a generic way to bypass it.

February 7, 2019

Telerik Revisited

In 2017, several vulnerabilities were discovered in Telerik UI, a popular UI component library for .NET web applications. Although details and working exploits are public, it often proves to be a good idea to take a closer look at it. Because sometimes it allows you to explore new avenues of exploitation.

July 6, 2018

LethalHTA - A new lateral movement technique using DCOM and HTA

The following blog post introduces a new lateral movement technique that combines the power of DCOM and HTA. The research on this technique is partly an outcome of our recent research efforts on COM Marshalling: Marshalling to SYSTEM - An analysis of CVE-2018-0824.