Adversaries may use NTFS file attributes to hide their malicious data in order to evade detection. Every New Technology File System (NTFS) formatted partition contains a Master File Table (MFT) that maintains a record for every file/directory on the partition. (Citation: SpectorOps Host-Based Jul 2017) Within MFT entries are file attributes, (Citation: Microsoft NTFS File Attributes Aug 2010) such as Extended Attributes (EA) and Data [known as Alternate Data Streams (ADSs) when more than one Data attribute is present], that can be used to store arbitrary data (and even complete files). (Citation: SpectorOps Host-Based Jul 2017) (Citation: Microsoft File Streams) (Citation: MalwareBytes ADS July 2015) (Citation: Microsoft ADS Mar 2014)

Adversaries may store malicious data or binaries in file attribute metadata instead of directly in files. This may be done to evade some defenses, such as static indicator scanning tools and anti-virus. (Citation: Journey into IR ZeroAccess NTFS EA) (Citation: MalwareBytes ADS July 2015)
NTFS File Attributes
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1564/004  external_id: T1564.004     source_name: MalwareBytes ADS July 2015  description: Arntz, P. (2015, July 22). Introduction to Alternate Data Streams. Retrieved March 21, 2018.  url: https://blog.malwarebytes.com/101/2015/07/introduction-to-alternate-data-streams/     source_name: SpectorOps Host-Based Jul 2017  description: Atkinson, J. (2017, July 18). Host-based Threat Modeling & Indicator Design. Retrieved March 21, 2018.  url: https://posts.specterops.io/host-based-threat-modeling-indicator-design-a9dbbb53d5ea     source_name: Journey into IR ZeroAccess NTFS EA  description: Harrell, C. (2012, December 11). Extracting ZeroAccess from NTFS Extended Attributes. Retrieved June 3, 2016.  url: http://journeyintoir.blogspot.com/2012/12/extracting-zeroaccess-from-ntfs.html     source_name: Microsoft NTFS File Attributes Aug 2010  description: Hughes, J. (2010, August 25). NTFS File Attributes. Retrieved March 21, 2018.  url: https://blogs.technet.microsoft.com/askcore/2010/08/25/ntfs-file-attributes/     source_name: Microsoft ADS Mar 2014  description: Marlin, J. (2013, March 24). Alternate Data Streams in NTFS. Retrieved March 21, 2018.  url: https://blogs.technet.microsoft.com/askcore/2013/03/24/alternate-data-streams-in-ntfs/     source_name: Microsoft File Streams  description: Microsoft. (n.d.). File Streams. Retrieved December 2, 2014.  url: http://msdn.microsoft.com/en-us/library/aa364404     source_name: Oddvar Moe ADS2 Apr 2018  description: Moe, O. (2018, April 11). Putting Data in Alternate Data Streams and How to Execute It - Part 2. Retrieved June 30, 2018.  url: https://oddvar.moe/2018/04/11/putting-data-in-alternate-data-streams-and-how-to-execute-it-part-2/     source_name: Oddvar Moe ADS1 Jan 2018  description: Moe, O. (2018, January 14). Putting Data in Alternate Data Streams and How to Execute It. Retrieved June 30, 2018.  url: https://oddvar.moe/2018/01/14/putting-data-in-alternate-data-streams-and-how-to-execute-it/     source_name: Symantec ADS May 2009  description: Pravs. (2009, May 25). What you need to know about alternate data streams in windows? Is your Data secure? Can you restore that?. Retrieved March 21, 2018.  url: https://www.symantec.com/connect/articles/what-you-need-know-about-alternate-data-streams-windows-your-data-secure-can-you-restore     