Vulnerability – Sec Team Blog

CVE-2022-41099 – Analysis of a BitLocker Drive Encryption Bypass

In November 2022, an advisory was published by Microsoft about a BitLocker bypass. This vulnerability caught my attention because the fix required a manual operation by users and system administrators, even after installing all the security updates. Couple this with the fact that the procedure was not well documented initially, and you have the perfect recipe for disaster.

This is typically the kind of vulnerability you do not want to deal with when you are in charge of a large fleet of workstations and laptops. However, on the other side of things, hard to patch vulnerabilities such as this one usually offer the best opportunities for red teamers and the like. This is where my journey investigating this bug and learning more about TPM-based BitLocker Drive Encryption began.

Producing a POC for CVE-2022-42475 (Fortinet RCE)

Late last year a new remote code execution vulnerability was discovered in Fortinet’s SSLVPN service. Given the relative lack of information surrounding it at the time, and the fact I’d have some uninterrupted research time due to a lengthy flight, I decided to attempt to produce a POC for the vulnerability.

Stealing user passwords through a VPN’s SSO

Last year I got this idea that I should attempt to pay for my holidays to Japan by hunting for bounties in security appliances while in the plane. A full 10 hours of uninterrupted focus on one solution seemed like it should yield interesting results. So I started reverse engineering the Firewall of a relatively common brand which has a private bug bounty. Due to this reason, I won’t be giving out the full details of the issue I discovered, but I find the vulnerability to be quite interesting and worth discussing. So I attempt to do this here without breaching any disclosure terms…

Combining Request Smuggling and CBC Byte-flipping to stored-XSS

During a recent penetration test we stumbled upon a couple of issues which independently might not have warranted any attention, but when combined allowed to compromise other users by injecting arbitrary JavaScript into their browsers. It goes to show that even certain issues which might not always seem particularly interesting (such as self-XSS) can sometimes be exploited in meaningful ways. I’ll keep this mostly theoretical so as not to divulge any information on the actual targeted system.

SonicWall SRA and SMA vulnerabilities

Last year, Orange Tsai did some awesome research and discovered several vulnerabilities in SSL VPN providers which can allow an attacker to break into a network through the very device which is supposed to protect it. The vulnerable constructors were:

Palo Alto
Fortinet
Pulse Secure

Magento – RCE & Local File Read with low privilege admin rights

I regularly search for vulnerabilities on big services that allow it and have a Bug Bounty program. Here is a second paper which covers two vulnerabilities I discovered on Magento, a big ecommerce CMS that’s now part of Adobe Experience Cloud. These vulnerabilities have been responsibly disclosed to Magento team, and patched for Magento 2.3.0, 2.2.7 and 2.1.16.

PHPMyAdmin multiple vulnerabilities

During an assignment, I found several serious vulnerabilities in phpMyAdmin, which is an application massively used to manage MariaDB and MySQL databases. One of them potentially leads to arbitrary code execution by exploiting a Local file inclusion, while the other is a CSRF allowing any table entry to be edited.

Remote Code Execution on a Facebook server

I regularly search for vulnerabilities on big services that allow it and have a Bug Bounty program. Here is my first paper which covers a vulnerability I discovered on one of Facebook’s servers.

While scanning an IP range that belongs to Facebook (199.201.65.0/24), I found a Sentry service hosted on 199.201.65.36, with the hostname sentryagreements.thefacebook.com. Sentry is a log collection web application, written in Python with the Django framework.

WPA2 KRACK – What you should know so far … (in simple terms)

As most people, we have been waiting for the release of the technical details surrounding the WPA2 vulnerabilities discovered by Mathy Vanhoef (@vanhoefm).

While the details and the full paper (https://papers.mathyvanhoef.com/ccs2017.pdf) are now available, here is a summary aimed at providing the big picture as well as a few recommendations about this attack.

A pentester’s take on (Not)Petya

By now, everybody has probably read many articles on the latest viral outbreak, ranging from detailed analysis of the virus itself to rants about why companies don’t apply updates in a timely fashion and why employees continue to open malicious attachments in emails.