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Showing posts from 2020

QuickSand document malware similarity clustering

One of the most powerful features of is the ability to identify similar malware samples. We can use both the structhash (an md5 based on the structure of the document) and struzzy fuzzy hash to cluster samples. In this example, we will start with 500 recent samples of document malware with at least 10 detections on VirusTotal and write some python to count the number of unique similarity hashes. If two documents have the same structhush they likely originate from the same criminal or APT group or were generated from the same tool. We will build clusters to quickly group our 500 samples into buckets of similar samples to see what the main threats are. Out of the 500 randomly selected malware documents, we can quickly see some clusters with up to 76 samples with an identical structure denoted by an identical stucthash. We can use the fuzzy hash struzzy to squeeze out a few more similarities into the clusters as well. These samples might have a few minor differences as objec

QuickSand 2

The 2020 CSO Online survey revealed that 94% of malware is still delivered via email. We decided to refresh into an all in one tool for analyzing both documents and PDFs for malware. Over the last few years the state of document and PDF malware has shifted dramatically from exploits to active content, exploiting the features of Office and PDF documents to deliver malware. The web version of is a simplified result to determine if the analyzed document has active content, high risk active content, or a potential exploit. We do recommend blocking active content from external email as much as possible. Get Started On any page on click the `Choose File` button under the logo on the left, then select the file to scan. Click `Scan Document or PDF` to start the analysis. Javascript is required to upload the file. Limits Filesize: 10MB. Documents over 10MB (max 28s of processing) or PDFs over 5MB (max 18s of processing) may timeout on the online version 2.0.1 major release

Check out our new version of Now supports PDF and documents (Office OLE/OpenOffice and RTF) all in a single tool. We now use a risk description to define the risk from each document. Generally documents or PDFs will have either active content like macros or scripts, or contain an exploit.