In my ordinary life, I teach computer science at the University of Applied Sciences in Mannheim but for some months, I was an intern at ERNW learning a lot about IT security and penetration testing. One of these learnings is that old protocols can be fun and breaking them even more. But let’s start at the beginning of the story…
Back in the year 1986: Top Gun, Platoon, and Crocodile Dundee were the top-grossing films in the cinema and IBM sold the very first laptop computer, called IBM PC Convertible (model 5140). The Internet Engineering Task Force (IETF) was just founded and Boris Becker won the Wimbledon Championships for the second time. A group of engineers of the Organisation for Data Exchange by Tele Transmission in Europe (ODETTE) met and specified OFTP, a protocol to transfer files over … no, there was no Internet commercially available at that time … X.25 networks. X.25 itself dates back to 1976 and is a packet-switched protocol for WANs. The OFTP protocol tried to “address the electronic data interchange (EDI) requirements of the European automotive industry” RFC2204, page 3. With the rise of the Internet, OFTP was extended in 1997 to support TCP/IP in addition to X.25 as the transport protocol (RFC2204) and in 2007 again to include encryption and authentication (RFC5024). With RFC5024 we have the most recent specification of the protocol which is called “OFTP2”. They somehow skipped their 10-year cycle (86, 97, 07) and did not release a current specification in the last 14 years.
Recently, I had a brief look at the Froala WYSIWYG HTML Editor (v3.2.0) as there was a post about it on the Full Disclosure mailing list.
When targeting a HTML Editor, I guess one of the first things that everybody does is to check for XSS vulnerabilities. So I tried the usual XSS payloads (a great resource for XSS payloads is the XSS cheat sheet by PortSwigger) within the editor’s code view, but did not have much luck with the common payloads as they were filtered. However, using the HTML object tag, it was possible to trigger an XSS.
OpenSIS is an open source student information system. Recently, it was affected by several vulnerabilities such as SQL injections, local file inclusions and incorrect access controls (CVE-2020-13380, CVE-2020-13381, CVE-2020-13382, CVE-2020-13383). That is why I got interested and also had a quick look at the application.
As part of this investigation, I discovered two vulnerabilities, an XSS vulnerability (CVE-2020-27409) in the file SideForStudent.php that got quickly fixed after being reported (see commit edca085 for the details; the commit is included in release v7.5) and some incorrect (i.e. non-existent) access controls for the password change functionality (CVE-2020-27408). In this blog post, I would like to focus on the second vulnerability and describe the tedious disclosure process that – in the end – lead to nothing but the implementation of some ineffective obfuscation mechanism. Continue reading “OpenSIS Vulnerabilities”
I should start by telling you that this post does not contain anything fundamentally new. Hence, if you already know the tools mentioned in the title, this post may probably not be for you. However, if you are not too familiar with these tools and want to understand a little bit more on how they work together, you should keep on reading.
First, let us get a high-level overview of the different tools. We begin with QEMU. QEMU is a piece of software to emulate hardware such as processors. Imagine, for example, that you are running an operating system such as Linux or Windows on a x86-64 machine and that you would like to analyze a binary that has been compiled for an ARM or MIPS processor. Of course, you can use static analysis on the binary, but if you want to find out more about the runtime behavior, well, it would be good to have a corresponding runtime environment. Continue reading “QEMU, Unicorn, Zelos, and AFL”
During security assessments we sometimes obtain access to a restricted shell on a target system. To advance further and gain complete control of the system, the next step is usually to break out of this shell. If the restricted shell provides access to certain system binaries, these binaries can often be exploited to perform such a break out. Here we would like to show an interesting example of such a break out by using the tcpdump binary. Continue reading “How to break out of restricted shells with tcpdump”
Again, Cisco released security advisories for their software-defined networking (SDN) solution called Application Centric Infrastructure (ACI). As before (see blog post here), the published advisories originated from research performed in our ACI lab. Continue reading “Security Advisories for Cisco ACI”
Once again Troopers will have its Windows & Linux Binary Exploitation workshop. Its main focus are the ever-present stack-based buffer overflows still found in software today (e.g. CVE-2018-5002, CVE-2018-1459, and CVE-2018-12897) and their differences with regard to exploitation on Windows and Linux systems. If you ever wanted to know the details of the exploit development process for these systems then this workshop is for you. Continue reading “TROOPERS19 Training Teaser: Windows & Linux Binary Exploitation”
During a recent customer project we identified several vulnerabilities in the VMware vRealize Automation Center such as a DOM-based cross-site scripting and a missing renewal of session tokens during the login. The vulnerabilities have been disclosed to VMware on November 20th, 2017. A security advisory for the vulnerabilities has been made available here on April 12th, 2018. Continue reading “Security Advisory for VMware vRealize Automation Center”
Last year I encountered a slight variation of an internal port scan vulnerability for the CrystalReports component of SAP Business Objects. The original vulnerability was presented and disclosed by rapid7 in the talk “Hacking SAP Business Objects”. The corresponding slides can be found here. Continue reading “Information About SAP Security Note 2336795”