Bypassing Windows API hooking with syscalls

by Marcelo Benesciutti Recently I started to do some researches on AV/EDR bypass and Windows internals (shoutout to my friend Thiago Peixoto on this part, who have helped me alot). On my studies I have stumbled on a very common detection method employed by most AV/EDR solutions, Windows API hooking. Basically, the solutions hook common functions used on malicious code, such as OpenProcess, VirtualAllocEx, WriteProcessMemory, CreateRemoteThread, among others, and if an unknown PE makes use of these functions, it will be potentially flagged as malicious. …

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mXSS in support.mozilla.org

by Guilherme Keerok This is another bug that was discovered during @duphouse, and was the result of a collaboration with @lbherrera. It was found on Kitsune, which is an open-source software that runs SUMO (support.mozilla.org), and provides support for Firefox and other Mozilla software. It works similarly to a wiki, containing several functionalities for users to create, read or edit articles. During the tests, the preview functionality caught our attention, as it allowed users to preview their changes to the article before submitting it - and more interestingly - it was also allowing a small subset of HTML tags to be included that got rendered inside the page. …

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Three Microsoft Store vulnerabilites

Author: Marlon Fabiano Description of the 3 vulnerabilities: “Generating invoices in the Microsoft Store without making purchases”, “Adding money in the Microsoft Store Wallet” and “Buying Definitive / Deluxe / Ultimate games for the price of a standard game”. The summary of the steps of the two Bypass (purchases of infinite games and subscriptions within Microsoft’s sandbox) can be found at the link: https://github.com/smarlonfabiano/xbox_xpl Vulnerability 1 Understanding the vulnerability that allows you to generate invoices for Xbox games without buying them and the possibility to profit through the Nota Fiscal Paulista. …

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Microsoft Store free purschase vulnerabilites

Author: Marlon Fabiano First bypass - Free Vulnerability Purchases Microsoft has an extensive BugBounty program. I have already participated a few times and received some acknowledgements on the MSRC (Microsoft Security Response Center) portal, so I identified a great bug in Microsoft’s payment method. A failure that allowed me to buy products from the store and not paying anything for it. It is important to mention that when I reported the failure to the MSRC it was not that simple, because the triage team ended up discrediting even with the PoCs (Proof Of Concept) of someone who said: “Hey Microsoft, I can subscribe to Xbox Live for free. …

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Pop-Ups in a good-world

by Guilherme Keerok Introduction This research was fun to do and I believe it addresses some cool and theoretically interesting techniques, some things have already been reported, and others, due to the format that these technologies were made, don’t need to be reported, as several techniques here are considered by design in browsers. One of the main themes that I tried to focus on this research was not to use CSRF so I tried to do something similar, maybe a “CSWF” (Cross-Site Window Forgery), this is just a joke, but yes, without CSRF but with a little bit of Clickjacking. …

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Object Injection to SQL Injection

by Walleson Moura (@phor3nsic_br) NodeJS + Sqlstring In this section, we will explain a curious case of sql injection, a possible scenario, details of the issue, possible impacts and mitigations. What is Object Injection? Object Injection is an application-level vulnerability that could allow an attacker to execute different types of malicious methods, such as Code Injection, SQL Injection, Path Traversal and Application Denial of Service, depending on the context. …

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A short story about an XSS in chat.mozilla.org (CVE-2021-21320)

by Guilherme Keerok In the last month, some friends and I have founded @duph0use, a house where we spent the last month doing bug bounties, researching, and working. At some point during the time I was there, I started searching for bugs in Mozilla, which led me to find 3 XSSes. In this post I will only be showing one of these findings. While I navigated through Mozilla products, I ended up finding chat. …

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