NTFS Files Attributes Antivirus/EDR Evasion

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. Within MFT entries are file attributes, such as Extended Attributes 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 …

Hide Artifacts: NTFS File Attributes Defense Evasion [Mitre]

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. Within MFT entries are file attributes, such as Extended Attributes (EA) and Data [known as Alternate Data Streams (ADSs) when …

Process Doppelgänging Process Manipulating

This technique leverages the Transactional NTFS functionality in Windows. This functionality helps maintain data integrity during an unexpected error. For example, when an application needs to write or modify a file, if an error is triggered mid-write, the data can be corrupted. To avoid this kind of behavior, an application can open the file in a transactional mode to perform …

Hide Artifacts: Hidden File System Defense Evasion [Mitre]

Adversaries may use a hidden file system to conceal malicious activity from users and security tools. File systems provide a structure to store and access data from physical storage. Typically, a user engages with a file system through applications that allow them to access files and directories, which are an abstraction from their physical location (ex: disk sector). Standard file …

Process Injection: Process Doppelgänging Defense Evasion [Mitre]

Adversaries may inject malicious code into process via process doppelgänging in order to evade process-based defenses as well as possibly elevate privileges. Process doppelgänging is a method of executing arbitrary code in the address space of a separate live process.

Windows Transactional NTFS (TxF) was introduced in Vista as a method to perform safe file operations. To ensure data …

Subvert Trust Controls: Mark-of-the-Web Bypass Defense Evasion [Mitre]

Adversaries may abuse specific file formats to subvert Mark-of-the-Web (MOTW) controls. In Windows, when files are downloaded from the Internet, they are tagged with a hidden NTFS Alternate Data Stream (ADS) named Zone.Identifier with a specific value known as the MOTW. Files that are tagged with MOTW are protected and cannot perform certain actions. For example, starting in MS Office …