Adversaries may modify file or directory permissions/attributes to evade access control lists (ACLs) and access protected files.(Citation: Hybrid Analysis Icacls1 June 2018)(Citation: Hybrid Analysis Icacls2 May 2018) File and directory permissions are commonly managed by ACLs configured by the file or directory owner, or users with the appropriate permissions. File and directory ACL implementations vary by platform, but generally explicitly designate which users or groups can perform which actions (read, write, execute, etc.).

Modifications may include changing specific access rights, which may require taking ownership of a file or directory and/or elevated permissions depending on the file or directory’s existing permissions. This may enable malicious activity such as modifying, replacing, or deleting specific files or directories. Specific file and directory modifications may be a required step for many techniques, such as establishing Persistence via [Accessibility Features](https://attack.mitre.org/techniques/T1546/008), [Boot or Logon Initialization Scripts](https://attack.mitre.org/techniques/T1037), [Unix Shell Configuration Modification](https://attack.mitre.org/techniques/T1546/004), or tainting/hijacking other instrumental binary/configuration files via [Hijack Execution Flow](https://attack.mitre.org/techniques/T1574).

Adversaries may also change permissions of symbolic links. For example, malware (particularly ransomware) may modify symbolic links and associated settings to enable access to files from local shortcuts with remote paths.(Citation: new_rust_based_ransomware)(Citation: bad_luck_blackcat)(Citation: falconoverwatch_blackcat_attack)(Citation: blackmatter_blackcat)(Citation: fsutil_behavior) 
File and Directory Permissions Modification
source_name: mitre-attack  url: https://attack.mitre.org/techniques/T1222  external_id: T1222     source_name: falconoverwatch_blackcat_attack  description: Falcon OverWatch Team. (2022, March 23). Falcon OverWatch Threat Hunting Contributes to Seamless Protection Against Novel BlackCat Attack. Retrieved May 5, 2022.  url: https://www.crowdstrike.com/blog/falcon-overwatch-contributes-to-blackcat-protection/     source_name: Hybrid Analysis Icacls1 June 2018  description: Hybrid Analysis. (2018, June 12). c9b65b764985dfd7a11d3faf599c56b8.exe. Retrieved August 19, 2018.  url: https://www.hybrid-analysis.com/sample/ef0d2628823e8e0a0de3b08b8eacaf41cf284c086a948bdfd67f4e4373c14e4d?environmentId=100     source_name: Hybrid Analysis Icacls2 May 2018  description: Hybrid Analysis. (2018, May 30). 2a8efbfadd798f6111340f7c1c956bee.dll. Retrieved August 19, 2018.  url: https://www.hybrid-analysis.com/sample/22dab012c3e20e3d9291bce14a2bfc448036d3b966c6e78167f4626f5f9e38d6?environmentId=110     source_name: bad_luck_blackcat  description: Kaspersky Global Research & Analysis Team (GReAT). (2022). A Bad Luck BlackCat. Retrieved May 5, 2022.  url: https://go.kaspersky.com/rs/802-IJN-240/images/TR_BlackCat_Report.pdf     source_name: fsutil_behavior  description: Microsoft. (2021, September 27). fsutil behavior. Retrieved January 14, 2022.  url: https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/fsutil-behavior     source_name: EventTracker File Permissions Feb 2014  description: Netsurion. (2014, February 19). Monitoring File Permission Changes with the Windows Security Log. Retrieved August 19, 2018.  url: https://www.eventtracker.com/tech-articles/monitoring-file-permission-changes-windows-security-log/     source_name: blackmatter_blackcat  description: Pereira, T. Huey, C. (2022, March 17). From BlackMatter to BlackCat: Analyzing two attacks from one affiliate. Retrieved May 5, 2022.  url: https://blog.talosintelligence.com/2022/03/from-blackmatter-to-blackcat-analyzing.html     source_name: new_rust_based_ransomware  description: Symantec Threat Hunter Team. (2021, December 16). Noberus: Technical Analysis Shows Sophistication of New Rust-based Ransomware. Retrieved January 14, 2022.  url: https://symantec-enterprise-blogs.security.com/blogs/threat-intelligence/noberus-blackcat-alphv-rust-ransomware     