It’s not a secret that we at Silent Signal are hopeless romantics, especially when it comes to classic Unix systems (1, 2, 3). Since some of these systems – that still run business critical applications at our clients – are based on some “exotic” architectures, we have a nice hardware...
2021-04-06 — 5 minute readThis blog post is dedicated to those to brave souls that dare to roll their own crypto The RSA Textbook of Horrors This story begins with an old project of ours, where we were tasked to verify (among other things) how a business application handles digital signatures of transactions, to...
2021-02-08 — 6 minute readOn a recent engagement our task was to assess the security of a service built on IBM Integration Bus, an integration platform for Java Messaging Services. These scary looking enterprise buzzwords usually hide systems of different complexities connected with Message Queues. Since getting arbitrary test data in and out of...
2020-08-17 — 8 minute readRenewal paper of my GIAC Web Application Penetration Tester certification: Tips and scripts for reconnaissance and scanning
2020-05-20 — 1 minute readSniffing plaintext network traffic between apps and their backend APIs is an important step for pentesters to learn about how they interact. In this blog post, we’ll introduce a method to simplify getting our hands on plaintext messages sent between apps ran on our attacker-controlled devices and the API, and...
2020-05-04 — 7 minute readWhile we at Silent Signal are strong believers in human creativity when it comes to finding new, or unusual vulnerabilities, we’re also constantly looking for ways to transform our experience into automated tools that can reliably and efficiently detect already known bug classes. The discovery of CVE-2019-6976 – an uninitialized...
2020-04-20 — 3 minute readSANS Institute accepted my GWAPT Gold Paper about Unix-style approach to web application testing, the paper is now published in the Reading Room. The paper introduces several problems I’ve been facing while testing web applications, which converged in a common direction. Burp Suite is known by most and used by...
2020-03-27 — 1 minute readWith the advent of PSD2 APIs, we had the opportunity to test some of them upon request from our clients. Although internet-facing APIs were already a thing thanks to smartphone apps, it seems that regulatory requirements and 3-way setups (customer, bank, provider) led to some surprises. Here are some of...
2020-01-27 — 4 minute read