In August 2023, Meta engaged NCC Group’s Cryptography Services practice to perform an implementation review of their Auditable Key Directory (AKD) library, which provides an append-only directory of public keys mapped to user accounts and a framework for efficient cryptographic validation of this directory by an auditor. The library is being leveraged to provide an AKD for WhatsApp and is meant to serve as a reference implementation for auditors of the WhatsApp AKD, as well as to allow other similar services to implement key transparency. The review was performed remotely by 3 consultants over a two-week period with a total of 20 person-days spent. The project concluded with a retest phase a few weeks after the original engagement that confirmed all findings were fixed.
Unveiling the Dark Side: A Deep Dive into Active Ransomware Families Author: Molly Dewis Intro Our technical experts have written a blog series focused on Tactics, Techniques and Procedures (TTP’s) deployed by four ransomware families recently observed during NCC Group’s incident response engagements. In case you missed it, our last…
Introduction If you are a pentester and enjoy tinkering with Windows, you have probably come across the following post by Raphael Mudge: Windows Access Tokens and Alternate Credentials In this post, he explains how the Windows program runas works and how the netonly flag allows the creation of processes where…
Overview Android 14 introduced a new feature which allows to remotely install CA certificates. This change implies that instead of using the /system/etc/security/cacerts directory to check the trusted CA’s, this new feature uses the com.android.conscrypt APEX module, and reads the certificates from the directory /apex/com.android.conscrypt/cacerts. Inspired by this blog post by Tim Perry,…