Сценарии инициализации при загрузке или входе в систему

ArcaneDoor used malicious boot scripts to install the Line Runner backdoor on victim devices.(Citation: Cisco ArcaneDoor 2024)

APT41 used a hidden shell script in `/etc/rc.d/init.d` to leverage the `ADORE.XSEC`backdoor and `Adore-NG` rootkit.(Citation: apt41_mandiant)

APT29 has hijacked legitimate application-specific startup scripts to enable malware to execute on system startup.(Citation: Mandiant APT29 Eye Spy Email Nov 22)

Depending on the Linux distribution and when executing with root permissions, RotaJakiro may install persistence using a `.conf` file in the `/etc/init/` folder.(Citation: RotaJakiro 2021 netlab360 analysis)

Rocke has installed an "init.d" startup script to maintain persistence.(Citation: Anomali Rocke March 2019)

Restrict write access to logon scripts to specific administrators. Prevent access to administrator accounts by mitigating Credential Access techniques and limiting account access and permissions of Valid Accounts. Identify and block potentially malicious software that may be executed through logon script modification by using whitelisting (Citation: Beechey 2010) tools like AppLocker (Citation: Windows Commands JPCERT) (Citation: NSA MS AppLocker) that are capable of auditing and/or blocking unknown programs.

Restricting registry permissions involves configuring access control settings for sensitive registry keys and hives to ensure that only authorized users or processes can make modifications. By limiting access, organizations can prevent unauthorized changes that adversaries might use for persistence, privilege escalation, or defense evasion. This mitigation can be implemented through the following measures: Review and Adjust Permissions on Critical Keys - Regularly review permissions on keys such as `Run`, `RunOnce`, and `Services` to ensure only authorized users have write access. - Use tools like `icacls` or `PowerShell` to automate permission adjustments. Enable Registry Auditing - Enable auditing on sensitive keys to log access attempts. - Use Event Viewer or SIEM solutions to analyze logs and detect suspicious activity. - Example Audit Policy: `auditpol /set /subcategory:"Registry" /success:enable /failure:enable` Protect Credential-Related Hives - Limit access to hives like `SAM`,`SECURITY`, and `SYSTEM` to prevent credential dumping or other unauthorized access. - Use LSA Protection to add an additional security layer for credential storage. Restrict Registry Editor Usage - Use Group Policy to restrict access to regedit.exe for non-administrative users. - Block execution of registry editing tools on endpoints where they are unnecessary. Deploy Baseline Configuration Tools - Use tools like Microsoft Security Compliance Toolkit or CIS Benchmarks to apply and maintain secure registry configurations. *Tools for Implementation* Registry Permission Tools: - Registry Editor (regedit): Built-in tool to manage registry permissions. - PowerShell: Automate permissions and manage keys. `Set-ItemProperty -Path "HKLM:\Software\Microsoft\Windows\CurrentVersion\Run" -Name "KeyName" -Value "Value"` - icacls: Command-line tool to modify ACLs. Monitoring Tools: - Sysmon: Monitor and log registry events. - Event Viewer: View registry access logs. Policy Management Tools: - Group Policy Management Console (GPMC): Enforce registry permissions via GPOs. - Microsoft Endpoint Manager: Deploy configuration baselines for registry permissions.

Restricting file and directory permissions involves setting access controls at the file system level to limit which users, groups, or processes can read, write, or execute files. By configuring permissions appropriately, organizations can reduce the attack surface for adversaries seeking to access sensitive data, plant malicious code, or tamper with system files. Enforce Least Privilege Permissions: - Remove unnecessary write permissions on sensitive files and directories. - Use file ownership and groups to control access for specific roles. Example (Windows): Right-click the shared folder → Properties → Security tab → Adjust permissions for NTFS ACLs. Harden File Shares: - Disable anonymous access to shared folders. - Enforce NTFS permissions for shared folders on Windows. Example: Set permissions to restrict write access to critical files, such as system executables (e.g., `/bin` or `/sbin` on Linux). Use tools like `chown` and `chmod` to assign file ownership and limit access. On Linux, apply: `chmod 750 /etc/sensitive.conf` `chown root:admin /etc/sensitive.conf` File Integrity Monitoring (FIM): - Use tools like Tripwire, Wazuh, or OSSEC to monitor changes to critical file permissions. Audit File System Access: - Enable auditing to track permission changes or unauthorized access attempts. - Use auditd (Linux) or Event Viewer (Windows) to log activities. Restrict Startup Directories: - Configure permissions to prevent unauthorized writes to directories like `C:\ProgramData\Microsoft\Windows\Start Menu`. Example: Restrict write access to critical directories like `/etc/`, `/usr/local/`, and Windows directories such as `C:\Windows\System32`. - On Windows, use icacls to modify permissions: `icacls "C:\Windows\System32" /inheritance:r /grant:r SYSTEM:(OI)(CI)F` - On Linux, monitor permissions using tools like `lsattr` or `auditd`.