File and Directory Permissions Modification T1222
Tactic: Defense Impairment
Adversaries may modify file or directory permissions/attributes to evade access control lists (ACLs) and access protected files. 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.).
Events covered
10 catalog events are tagged with this technique by at least one rule.
| Provider | Event | Title |
|---|---|---|
| Sysmon | Event ID 1 | Process creation |
| Security-Auditing | Event ID 4662 | An operation was performed on an object. |
| Security-Auditing | Event ID 4688 | A new process has been created. |
| Security-Auditing | Event ID 5124 | A security setting was updated on OCSP Responder Service. |
| Security-Auditing | Event ID 5136 | A directory service object was modified. |
| Security-Auditing | Event ID 5143 | A network share object was modified. |
| Linux-Auditd | Event ID 1309 | EXECVE |
| PowerShell | Event ID 4103 | Payload Context: ContextInfo User Data: UserData. |
| PowerShell | Event ID 4104 | Creating Scriptblock text (MessageNumber of MessageTotal). |
| Sysmon-for-Linux | Event ID 1 | Process Create |
Authoring guide
Patterns shared across the 79 rules above: which fields they filter on, what specific values they look for, and what they exclude. The catalog normalizes field names across vendors so Sigma's Image, Elastic's process.name, and Splunk's process_name collapse into one row. Each rule contributes at most once per row.
Fields filtered most (61 distinct)
The fields most rules look at when detecting this technique. The How column shows the operators authors use (eq, wildcard, regex_match, match) and how often each appears. Sample values are concrete examples to start from, not an exhaustive list.
Top indicator values (394 distinct)
Specific (field, operator, value) combinations the rules check for, ranked by how many rules under this technique use each one. The Corpus reach column counts how many rules across the entire catalog (any technique) check the same combination. High numbers point to widely-used indicators that are likely noisy on their own; combine them with another condition for useful signal. Blank means the combination is specific to rules under this technique. Click a value to expand the rules under this technique that use it.
Exclusions (165 distinct)
Field/operator/value combinations excluded by rules under this technique (top-level not() clauses), sorted by how many rules exclude each. These are the false-positive paths the community has learned to filter out. A new rule that ignores the high-count entries here will likely fire on the same noisy paths. Click a value to expand the rules under this technique that exclude it.
Rules under this technique
Every rule in the catalog tagged with this technique, grouped by vendor. Click a rule title for its full predicates, exclusions, and indicators.
Sigma 18 rules
- AD Object WriteDAC Access
- Chmod Targeting Sensitive Directories
- Computer account modifying Active Directory permissions
- Computer account modifying Active Directory permissions (PrivExchange)
- File or Folder Permissions Change
- File or Folder Permissions Modifications
- macOS Code Signature Invalidation
- macOS TCC Database Modification
- OCSP responder security settings changed
- Potentially Suspicious NTFS Symlink Behavior Modification
- PowerShell Script Change Permission Via Set-Acl - PsScript
- PowerShell Set-Acl On Windows Folder - PsScript
- Remove Immutable File Attribute
- Remove Immutable File Attribute - Auditd
- Replication privileges granted to perform DCSync attack
- Suspicious permissions modification on a network share
- Suspicious Recursive Takeown
- WannaCry Ransomware Activity
Elastic 17 rules
- Access Control List Modification via setfacl
- Adding Hidden File Attribute via Attrib
- Azure Blob Storage Container Access Level Modified
- Azure Blob Storage Permissions Modified
- Executable Bit Set for Potential Persistence Script
- File and Directory Permissions Modification
- File Creation in World-Writable Directory by Unusual Process
- File Execution Permission Modification Detected via Defend for Containers
- File made Immutable by Chattr
- File Permission Modification in Writable Directory
- GCP Storage Bucket Permissions Modification
- Potential Unauthorized Access via Wildcard Injection Detected
- Privilege Escalation via CAP_CHOWN/CAP_FOWNER Capabilities
- Suspicious File Made Executable via Chmod Inside A Container
- System Binary Path File Permission Modification
- System File Ownership Change
- WRITEDAC Access on Active Directory Object
Splunk 39 rules
- Excessive Usage Of Cacls App
- File_Folder Hidden - Windows (PowerShell)
- File_Folder Hidden - Windows (Sysmon)
- File_Folder Hidden - Windows (Windows Event Log)
- Full Control Permissions Granted to Everyone - Windows (Sysmon)
- Full Control Permissions Granted to Everyone - Windows (Windows Event Log)
- Hiding Files And Directories With Attrib exe
- Icacls Deny Command
- ICACLS Grant Command
- Linux Auditd Change File Owner To Root
- Linux Auditd File Permission Modification Via Chmod
- Linux Auditd File Permissions Modification Via Chattr
- Linux Change File Owner To Root
- Modify ACL permission To Files Or Folder
- Permission Modification using Takeown App
- Permissions Replaced by icacls - Windows (PowerShell)
- Permissions Replaced by icacls - Windows (Sysmon)
- Permissions Replaced by icacls - Windows (Windows Event Log)
- Read-Only Attribute Removed - Windows (PowerShell)
- Read-Only Attribute Removed - Windows (Sysmon)
- Read-Only Attribute Removed - Windows (Windows Event Log)
- Windows AD Dangerous Deny ACL Modification
- Windows AD Dangerous Group ACL Modification
- Windows AD Dangerous User ACL Modification
- Windows AD DCShadow Privileges ACL Addition
- Windows AD Domain Root ACL Deletion
- Windows AD Domain Root ACL Modification
- Windows AD GPO New CSE Addition
- Windows AD Hidden OU Creation
- Windows AD Object Owner Updated
- Windows AD Suspicious Attribute Modification
- Windows Common Abused Cmd Shell Risk Behavior
- Windows File and Directory Enable ReadOnly Permissions
- Windows File and Directory Permissions Enable Inheritance
- Windows File and Directory Permissions Remove Inheritance
- Windows Files and Dirs Access Rights Modification Via Icacls
- Windows SubInAcl Execution
- Windows SymbolicLink-Testing-Tools Utility Execution
- Windows Symlink Evaluation Change via Fsutil