netstat without netstat

Recently I was doing an assessment in a locked down and restricted environment. One of the first actions you tend to do when landing a shell on a [linux] box is to do some reconnaissance. This is both on host and network, as you want to determine what new access this host has given you. Normally you would run netstat, ifconfig, ip route etc to determine if the compromised host is connected to any other hosts and to determine if there are other network segments you do not know about....

December 20, 2017 · 6 min · 1267 words · Etienne Stalmans

Polycom HDX Series RCE

When doing external assessments you spend a decent amount of time footprinting your target and finding possible avenues of attack. Given a large corporate, you are pretty likely to hit video conferencing end-points. This post details a vulnerability in one of these video conferencing systems, the Polycom HDX series. I identified this vulnerability while still at SensePost and reported it to Polycom. The vulnerability was acknowledged and we were informed that a patch would be issued....

November 12, 2017 · 8 min · 1527 words · Etienne Stalmans

MSWord - Obfuscation with Field Codes

A few weeks back Saif El-Sherei and I posted on the SensePost blog about DDE and getting command exec in MSWord without macros. This post got way more attention than we initially expected it would. Since then DDE has been used in phishing and malware campaigns, as well as legitimate red-team engagements. With the rapid rise in attacks using DDE, detection has been stepped up and most AV engines have basic DDE detection built in....

October 23, 2017 · 11 min · 2339 words · Etienne Stalmans

Phishing with OAuth and o365/Azure

Typically phishing has provided a low tech approach to getting access to credentials and services. The mainfocus up until now has been on getting username&passwords or tricking users into executing code. Subsequently, user awareness has gone up and users are better at identifying suspicious pages. Experience has shown that the click-through rate on emails have remained high, while users have been (slightly) less likely to enter credentials and more likely to report the phishing page....

August 2, 2017 · 7 min · 1294 words · Etienne Stalmans

NAT-to-NAT VPN with WireGuard

A recent research project/idea required me to look into setting up a NAT-to-NAT VPN. The basic idea being that two NATed networks are able to communicate through a VPN and share resources. While researching possible VPN solutions, I remembered reading about WireGuard a new VPN that aims to be fast, secure and lightweight. This seemed like the perfect opportunity to both try out a new VPN implementation and accomplish the goals of the research project....

April 17, 2017 · 5 min · 988 words · Etienne Stalmans