Publications

CVE-2022-31813: Forwarding addresses is hard

26/07/2022 A few weeks ago, version 2.4.54 of Apache HTTPD server was released. It includes a fix for CVE-2022-31813, a vulnerability we identified in mod_proxy that could affect unsuspecting applications served by an Apache reverse proxy. Let's see why it is rated as low in the software changelog and why it still matters. TL;DR: when in doubt, patch!

The printer goes brrrrr!!!

25/05/2022 Network printers have been featured for the first time at Pwn2Own competition in Austin 2021. Three popular LaserJet printers were included in the completion: HP, Lexmark and Canon. During the event, we (Synacktiv) managed to compromise all of them allowing us to win the whole competition. In this post, we will focus on how we achieved code execution on the Canon printer.

elFinder: The story of a repwning

30/03/2022 We recently identified a path traversal issue in the elFinder software. It is assigned CVE identifier CVE-2022-26960. While the vulnerability is pretty classical, the story of its discovery is not. Keep on reading for the details.

Pwn2Own Austin 2021 : Defeating the Netgear R6700v3

25/03/2022 Twice a year ZDI organizes a competition where the goal is to hack hardware and software. During November 2021, in Austin, hackers tried to exploit hardware devices such as printers, routers, phones, home automation devices, NAS and more. This blogpost describes how we successfully took over a Netgear router from the WAN interface.

Heap tricks never get old - Insomni'hack teaser 2022

08/02/2022 The Synacktiv team participated in the Insomni'hack teaser 2022 last week-end and placed 9th out of 280 teams. The onetestament challenge was pretty interesting and taught me a few tricks so I have decided to write a detailed solution. In this writeup, I have tried to illustrate the thought process behind solving this challenge, rather than just the usual solve.py (which you can still find at the end of the article). Expect to see some (old) heap tricks and enjoy the read!

How to exploit CVE-2021-40539 on ManageEngine ADSelfService Plus

04/11/2021 During a penetration test we encountered the ManageEngine ADSelfService Plus (ADSS) solution. ADSS offers multiple functionalities such as managing password policies for administrators or self password reset/account unlock for Active Directory users. We decided to dig into this solution. However, our research barely started that a wild exploitation on this solution was announced. In this article we will explore the details of several vulnerabilities that allow an unauthenticated attacker to execute arbitrary code on the ...

Car hijacking swapping a single bit

26/10/2021 Used to interact with various ECU (Electronic Control Unit) in a car, the UDS (Unified Diagnostic Services) service is widely deployed by car constructors. This generic high level protocol is used to extract ECUs state, configure them or even update their firmware. When the implementation lacks cryptography support inside an ECU, the security level can decrease dramatically. This short blog post presents an hardware attack leveraging all diagnostic functions to an unauthorized tester.

macOS XPC Exploitation - Sandbox Share case study

08/09/2021 Usually we don't do blog posts about CTF challenges but we recently stumbled across a challenge that was a good opportunity to talk about several macOS/iOS internals, security mechanisms and exploit methods...

Your vulnerability is in another OEM!

02/09/2021 Among targets for the Pwn2own Tokyo 2020 was 2 NAS, the Synology DiskStation DS418play and Western Digital My Cloud Pro PR4100. We took a look at both, and quickly found out Western Digital PR4100 was vulnerable via its webserver. However, exploitation was not THAT easy (it was not that hard either) and ultimately it did not even mattered since the vulnerability was wiped by a major OS update pushed mere days before the contest. In the end, the vulnerable code we audited might not have even been written by Western D...

Exploitation of a double free vulnerability in Ubuntu shiftfs driver (CVE-2021-3492)

13/07/2021 This year again, the international contest Pwn2Own Vancouver took place in the beginning of April. Among the different categories, two major operating systems were suggested for the Local Escalation of Privilege category (LPE): Linux (Ubuntu) and Windows 10. This article describes how a Ubuntu kernel vulnerability was found and exploited during this contest allowing to gain root access from an unprivileged user.