Windows 11's KB5031455 update adds RAR and 7z support via libarchive, but DEVCORE discovered multiple vulnerabilities, including Heap Buffer Overflow and arbitrary file operations. Delayed patching also enables “Half-day” attacks, putting projects like ClickHouse at risk. A step forward in convenience—or a hidden security threat?
The research unveils a new attack surface in Windows by exploiting Best-Fit, an internal charset conversion feature. Through our work, we successfully transformed this feature into several practical attacks, including Path Traversal, Argument Injection, and even RCE, affecting numerous well-known applications!
This research continues to explore the attack surface of Kernel Streaming, delving into newly discovered vulnerabilities within another feature of Kernel Streaming and demonstrating how to leverage this bug class to successfully attack Windows 11. This topic was also presented at HEXACON 2024.
This research will discuss an overlooked attack surface that allowed us to find more than ten vulnerabilities within two months. Additionally, we will delve into a proxy-based logical vulnerability type that allows us to bypass most validations, enabling us to successfully exploit Windows 11 in Pwn2Own Vancouver 2024.
This article explores architectural issues within the Apache HTTP Server, highlighting several technical debts within Httpd, including 3 types of Confusion Attacks, 9 new vulnerabilities, 20 exploitation techniques, and over 30 case studies. The content includes, but is not limited to: 1. How a single ? can bypass Httpd's built-in access control and authentication. 2. How unsafe RewriteRules can escape the Web Root and access the entire filesystem. 3. How to leverage a piece of code from 1996 to transform an XSS into RCE.
While implementing PHP, the team did not notice the Best-Fit feature of encoding conversion within the Windows operating system. This oversight allows unauthenticated attackers to bypass the previous protection of CVE-2012-1823 by specific character sequences. Arbitrary code can be executed on remote PHP servers through the argument injection attack.
DEVCORE research team found a 9-year-old WAN bug on RouterOS, the product of MikroTik. Combined with another bug of the Canon printer, DEVCORE becomes the first team ever to successfully complete an attack chain in the brand new SOHO Smashup category of Pwn2Own. And DEVCORE also won the title of Master of Pwn in Pwn2Own Toronto 2022.
We identified Pre-auth RCE vulnerabilities in Canon printers (CVE-2023-0853, CVE-2023-0854) and also discovered Pre-auth RCE flaws in HP printers, which led to our achievement of the Master of Pwn title at Pwn2Own Toronto 2022. This article will detail the vulnerabilities and exploitation methods for both Canon and HP printers.
In 2021, we found Pre-auth RCE vulnerabilities(CVE-2022-24673 and CVE-2022-3942) in Canon and HP printers, and vulnerability(CVE-2021-44734) in Lexmark. We used these vulnerabilities to exploit Canon ImageCLASS MF644Cdw, HP Color LaserJet Pro MFP M283fdw and Lexmark MC3224i in Pwn2Own Austin 2021. Following we will describe the details of the Canon and HP vulnerabilities and exploitation.
With the prior knowledge in mind, I come up with a simple idea. It’s common to see multiple Exchange Servers in corporate networks for high availability and site resilience. Can we relay the NTLM authentication among Exchange Servers?
We have also proved this attack works naturally on Microsoft Exchange Server. By leveraging the default activated Exchange Active Monitoring service, we can enter HealthMailbox's mailbox without passwords!
ProxyShell: The exploit chain we demonstrated at Pwn2Own 2021 to take over Exchange and earn $200,000 bounty
ProxyOracle! The attack on Exchange Server to recover any user's password in plaintext format
ProxyLogon! The most severe and impactful vulnerability in the Exchange Server history ever.
This post is about my research this March, which talks about how I found vulnerabilities on a leading Mobile Device Management product and bypassed several limitations to achieve unauthenticated RCE. All the vulnerabilities have been reported to the vendor and got fixed in June. After that, we kept monitoring large corporations to track the overall fixing progress and then found that Facebook didn't keep up with the patch for more than 2 weeks, so we dropped a shell on Facebook and reported to their Bug Bounty program!
After Jenkins released the [Security Advisory](https://jenkins.io/security/advisory/2018-12-05/#SECURITY-595) and fixed the dynamic routing vulnerability on 2018-12-05, I started to organize my notes in order to write this Hacking Jenkins series. While reviewing notes, I found another exploitation way on a gadget that I failed to exploit before! Therefore, the part two is the story for that! This is also one of my favorite exploits and is really worth reading :)
This article is mainly about a brief security review on Jenkins in the last year. During this review, we found 5 vulnerabilities including: CVE-2018-1999002(Arbitrary file read vulnerability), CVE-2018-1000600(CSRF and missing permission checks in GitHub Plugin), CVE-2018-1999046(Unauthorized users could access agent logs), CVE-2018-1000861(Code execution through crafted URLs), CVE-2019-pending(Sandbox Bypass in Script Security and Pipeline Plugins)
We reported an overflow vulnerability in the base64 decode function of Exim on 5 February, 2018, identified as CVE-2018-6789. This bug exists since the first commit of exim, hence ALL versions are affected. According to our research, it can be leveraged to gain Pre-auth Remote Code Execution and at least 400k servers are at risk. Patched version 4.90.1 is already released and we suggest to upgrade exim immediately.
In order to leverage the vulnerabilities, we put part of efforts into review of Sandstorm's source codes, and tried to escape the sandbox to impact the whole server...
On 23 November, 2017, we reported two vulnerabilities to Exim. These bugs exist in the SMTP daemon and attackers do not need to be authenticated, including CVE-2017-16943 for a use-after-free (UAF) vulnerability, which leads to Remote Code Execution (RCE); and CVE-2017-16944 for a Denial-of-Service (DoS) vulnerability.
According to a public data reconnaissance, there are currently 1,217 FTA servers online around the world, most of which are located in the US, followed by Canada, Australia, UK, and Singapore. Determine from the domain name and SSL Certificate of these servers, FTA is widely used by governmental bodies, educational institutions, enterprises, including several well-known brands.
