Compass Security Blog

Offensive Defense

Tag: SharePoint

SharePoint: Collaboration vs. XSS

SharePoint is a very popular browser-based collaboration and content management platform. Due to its high complexity, proprietary technology and confusing terminology it is often perceived as a black-box that IT and security professionals do not feel very comfortable with. These days, web security topics are well understood by many security professionals, penetration testers and vendors. But what […]

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SharePoint: How to collaborate with external parties?

Opening up an internal SharePoint farm to the Internet in order to share resources with external parties might seem a good idea, because it helps avoiding expensive infrastructure changes. However, in terms of security, this is not recommended because it does not sufficiently protect internal resources from external threats. The protection of internal resources hinges […]

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Wrap-up: Hack-Lab 2017#1

What is a Hack-Lab? Compass Security provides a monthly playful occasion for the security analysts to get-together and try to hack new devices, dive into current technologies and share their skills with their fellows. This also includes the improvement of internal tools, the research of newly identified publicly known attacks, and security analysis of hardware […]

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Excuse me, where is the best site of the city? After the DOM, just turn right!

During a SharePoint 2013 penetration test I performed last November, I noticed that a dynamically constructed JavaScript constantly fetched content or redirected me to the requested pages. Using a variation of the double-slash trick we exploited in the past, I misused this functionality in order to perform a DOM based open redirection attack. Every SharePoint […]

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Microsoft Security Bulletin MS13-067 – Critical

As part of today’s monthly patch day, Microsoft fixed an issue I reported in September 2012 around (ASP).NET and SharePoint. The vulnerability opens a new type of attack surface on ASP.NET if a given precondition regarding the Viewstate field is met. The impact is at least a breach of data integrity on the server side resulting […]

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