CISA AA24-241A

• Windows Abused Web Services :
  endpoint Endpoint risk_score:36 2024-09-30 version:3
  The following analytic detects a suspicious process making DNS queries to known, abused web services such as text-paste sites, VoIP, secure tunneling, instant messaging, and digital distribution platforms. This detection leverages Sysmon logs with Event ID 22, focusing on specific query names. This activity is significant as it may indicate an adversary attempting to download malicious files, a common initial access technique. If confirmed malicious, this could lead to unauthorized code execution, data exfiltration, or further compromise of the target host.


• Access to Vulnerable Ivanti Connect Secure Bookmark Endpoint :
  network VPN Appliance risk_score:72 2024-09-30 version:3
  The following analytic identifies access to the /api/v1/configuration/users/user-roles/user-role/rest-userrole1/web/web-bookmarks/bookmark endpoint, which is associated with CVE-2023-46805 and CVE-2024-21887 vulnerabilities. It detects this activity by monitoring for GET requests that receive a 403 Forbidden response with an empty body. This behavior is significant as it indicates potential exploitation attempts against Ivanti Connect Secure systems. If confirmed malicious, attackers could exploit these vulnerabilities to gain unauthorized access or control over the affected systems, leading to potential data breaches or system compromise.


• Windows Enable PowerShell Web Access :
  endpoint Endpoint risk_score:72 2024-09-30 version:3
  The following analytic detects the enabling of PowerShell Web Access via PowerShell commands. It leverages PowerShell script block logging (EventCode 4104) to identify the execution of the `Install-WindowsFeature` cmdlet with the `WindowsPowerShellWebAccess` parameter. This activity is significant because enabling PowerShell Web Access can facilitate remote execution of PowerShell commands, potentially allowing an attacker to gain unauthorized access to systems and networks.


• Ivanti Connect Secure Command Injection Attempts :
  network VPN Appliance risk_score:90 2024-09-30 version:4
  The following analytic identifies attempts to exploit the CVE-2023-46805 and CVE-2024-21887 vulnerabilities in Ivanti Connect Secure. It detects POST requests to specific URIs that leverage command injection to execute arbitrary commands. The detection uses the Web datamodel to monitor for these requests and checks for a 200 OK response, indicating a successful exploit attempt. This activity is significant as it can lead to unauthorized command execution on the server. If confirmed malicious, attackers could gain control over the system, leading to potential data breaches or further network compromise.


• Wsmprovhost LOLBAS Execution Process Spawn :
  endpoint Endpoint risk_score:54 2024-09-30 version:3
  The following analytic identifies `Wsmprovhost.exe` spawning a LOLBAS execution process. It leverages Endpoint Detection and Response (EDR) data to detect when `Wsmprovhost.exe` spawns child processes that are known LOLBAS (Living Off the Land Binaries and Scripts) executables. This activity is significant because it may indicate an adversary using Windows Remote Management (WinRM) to execute code on remote endpoints, a common technique for lateral movement. If confirmed malicious, this could allow attackers to execute arbitrary code, escalate privileges, or maintain persistence within the environment.


• Detect Remote Access Software Usage Registry :
  endpoint Endpoint risk_score:25 2024-11-21 version:1
  The following analytic detects when a known remote access software is added to common persistence locations on a device within the environment. Adversaries use these utilities to retain remote access capabilities to the environment. Utilities in the lookup include AnyDesk, GoToMyPC, LogMeIn, TeamViewer and much more. Review the lookup for the entire list and add any others.


• Detect Remote Access Software Usage File :
  endpoint Endpoint risk_score:25 2024-09-30 version:4
  The following analytic detects the writing of files from known remote access software to disk within the environment. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on file path, file name, and user information. This activity is significant as adversaries often use remote access tools like AnyDesk, GoToMyPC, LogMeIn, and TeamViewer to maintain unauthorized access. If confirmed malicious, this could allow attackers to persist in the environment, potentially leading to data exfiltration, further compromise, or complete control over affected systems.


• Windows Create Local Account :
  endpoint Endpoint risk_score:18 2024-09-30 version:4
  The following analytic detects the creation of a new local user account on a Windows system. It leverages Windows Security Audit logs, specifically event ID 4720, to identify this activity. Monitoring the creation of local accounts is crucial for a SOC as it can indicate unauthorized access or lateral movement within the network. If confirmed malicious, this activity could allow an attacker to establish persistence, escalate privileges, or gain unauthorized access to sensitive systems and data.


• Windows Modify Registry Delete Firewall Rules :
  endpoint Endpoint risk_score:64 2024-12-08 version:3
  The following analytic detects a potential deletion of firewall rules, indicating a possible security breach or unauthorized access attempt. It identifies actions where firewall rules are removed using commands like netsh advfirewall firewall delete rule, which can expose the network to external threats by disabling critical security measures. Monitoring these activities helps maintain network integrity and prevent malicious attacks.


• Windows Modify Registry to Add or Modify Firewall Rule :
  endpoint Endpoint risk_score:25 2024-12-08 version:4
  The following analytic detects a potential addition or modification of firewall rules, signaling possible configuration changes or security policy adjustments. It tracks commands such as netsh advfirewall firewall add rule and netsh advfirewall firewall set rule, which may indicate attempts to alter network access controls. Monitoring these actions ensures the integrity of firewall settings and helps prevent unauthorized network access.


• Ngrok Reverse Proxy on Network :
  network Endpoint risk_score:50 2024-09-30 version:3
  The following analytic detects DNS queries to common Ngrok domains, indicating potential use of the Ngrok reverse proxy tool. It leverages the Network Resolution datamodel to identify queries to domains such as "*.ngrok.com" and "*.ngrok.io". While Ngrok usage is not inherently malicious, it has been increasingly adopted by adversaries for covert communication and data exfiltration. If confirmed malicious, this activity could allow attackers to bypass network defenses, establish persistent connections, and exfiltrate sensitive data, posing a significant threat to the network's security.


• Citrix ADC Exploitation CVE-2023-3519 :
  endpoint Network risk_score:45 2024-10-17 version:4
  The following analytic identifies potential exploitation attempts against Citrix ADC related to CVE-2023-3519. It detects POST requests to specific web endpoints associated with this vulnerability by leveraging the Web datamodel. This activity is significant as CVE-2023-3519 involves a SAML processing overflow issue that can lead to memory corruption, posing a high risk. If confirmed malicious, attackers could exploit this to execute arbitrary code, escalate privileges, or disrupt services, making it crucial for SOC analysts to monitor and investigate these alerts promptly.


• Suspicious Scheduled Task from Public Directory :
  endpoint Endpoint risk_score:35 2024-09-30 version:3
  The following analytic identifies the creation of scheduled tasks that execute binaries or scripts from public directories, such as users\public, \programdata\, or \windows\temp, using schtasks.exe with the /create command. It leverages Sysmon Event ID 1 data to detect this behavior. This activity is significant because it often indicates an attempt to maintain persistence or execute malicious scripts, which are common tactics in malware deployment. If confirmed as malicious, this could lead to data compromise, unauthorized access, and potential lateral movement within the network.


• Windows IIS Server PSWA Console Access :
  network Web Server risk_score:32 2024-10-17 version:2
  This analytic detects access attempts to the PowerShell Web Access (PSWA) console on Windows IIS servers. It monitors web traffic for requests to PSWA-related URIs, which could indicate legitimate administrative activity or potential unauthorized access attempts. By tracking source IP, HTTP status, URI path, and HTTP method, it helps identify suspicious patterns or brute-force attacks targeting PSWA. This detection is crucial for maintaining the security of remote PowerShell management interfaces and preventing potential exploitation of this powerful administrative tool.


• Detect Remote Access Software Usage URL :
  network Network risk_score:25 2024-09-30 version:4
  The following analytic detects the execution of known remote access software within the environment. It leverages network logs mapped to the Web data model, identifying specific URLs and user agents associated with remote access tools like AnyDesk, GoToMyPC, LogMeIn, and TeamViewer. This activity is significant as adversaries often use these utilities to maintain unauthorized remote access. If confirmed malicious, this could allow attackers to control systems remotely, exfiltrate data, or further compromise the network, posing a severe security risk.


• Detect Remote Access Software Usage DNS :
  endpoint Endpoint risk_score:4 2024-09-30 version:4
  The following analytic detects DNS queries to domains associated with known remote access software such as AnyDesk, GoToMyPC, LogMeIn, and TeamViewer. This detection is crucial as adversaries often use these tools to maintain access and control over compromised environments. Identifying such behavior is vital for a Security Operations Center (SOC) because unauthorized remote access can lead to data breaches, ransomware attacks, and other severe impacts if these threats are not mitigated promptly.


• Disable Defender AntiVirus Registry :
  endpoint Endpoint risk_score:49 2024-12-08 version:8
  The following analytic detects the modification of Windows Defender registry settings to disable antivirus and antispyware protections. It leverages data from the Endpoint.Registry data model, specifically monitoring changes to registry paths associated with Windows Defender policies. This activity is significant because disabling antivirus protections is a common tactic used by adversaries to evade detection and maintain persistence on compromised systems. If confirmed malicious, this action could allow attackers to execute further malicious activities undetected, leading to potential data breaches, system compromise, and further propagation of malware within the network.


• Detect New Local Admin account :
  access Windows risk_score:42 2024-12-12 version:6
  The following analytic detects the creation of new accounts elevated to local administrators. It uses Windows event logs, specifically EventCode 4720 (user account creation) and EventCode 4732 (user added to Administrators group). This activity is significant as it indicates potential unauthorized privilege escalation, which is critical for SOC monitoring. If confirmed malicious, this could allow attackers to gain administrative access, leading to unauthorized data access, system modifications, and disruption of services. Immediate investigation is required to mitigate risks and prevent further unauthorized actions.


• WinEvent Windows Task Scheduler Event Action Started :
  endpoint Endpoint risk_score:80 2024-10-24 version:5
  The following analytic detects the execution of tasks registered in Windows Task Scheduler by monitoring EventID 200 (action run) and 201 (action completed) from the Task Scheduler logs. This detection leverages Task Scheduler logs to identify potentially suspicious or unauthorized task executions. Monitoring these events is significant for a SOC as it helps uncover evasive techniques used for persistence, unauthorized code execution, or other malicious activities. If confirmed malicious, this activity could lead to unauthorized access, data exfiltration, or the execution of harmful payloads, posing a significant threat to the environment.


• Create local admin accounts using net exe :
  endpoint Endpoint risk_score:30 2024-11-26 version:13
  The following analytic detects the creation of local administrator accounts using the net.exe command. It leverages Endpoint Detection and Response (EDR) data to identify processes named net.exe or net1.exe with the "/add" parameter and keywords related to administrator accounts. This activity is significant as it may indicate an attacker attempting to gain persistent access or escalate privileges. If confirmed malicious, this could lead to unauthorized access, data theft, or further system compromise. Review the process details, user context, and related artifacts to determine the legitimacy of the activity.


• F5 BIG-IP iControl REST Vulnerability CVE-2022-1388 :
  network Web Server risk_score:70 2024-09-30 version:3
  The following analytic detects attempts to exploit the F5 BIG-IP iControl REST API vulnerability (CVE-2022-1388) for unauthenticated remote code execution. It identifies suspicious URI paths and POST HTTP methods, along with specific request headers containing potential commands in the `utilcmdargs` field and a random base64 encoded value in the `X-F5-Auth-Token` field. This activity is significant as it targets a critical vulnerability that can allow attackers to execute arbitrary commands on the affected system. If confirmed malicious, this could lead to full system compromise and unauthorized access to sensitive data.


• Powershell Disable Security Monitoring :
  endpoint Endpoint risk_score:25 2024-11-26 version:6
  The following analytic identifies attempts to disable Windows Defender real-time behavior monitoring via PowerShell commands. It detects the use of specific `Set-MpPreference` parameters that disable various security features. This activity is significant as it is commonly used by malware such as RATs, bots, or Trojans to evade detection by disabling antivirus protections. If confirmed malicious, this action could allow an attacker to operate undetected, leading to potential data exfiltration, further system compromise, or persistent access within the environment.


• Possible Lateral Movement PowerShell Spawn :
  endpoint Endpoint risk_score:45 2024-10-17 version:7
  The following analytic detects the spawning of a PowerShell process as a child or grandchild of commonly abused processes like services.exe, wmiprsve.exe, svchost.exe, wsmprovhost.exe, and mmc.exe. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process and parent process names, as well as command-line executions. This activity is significant as it often indicates lateral movement or remote code execution attempts by adversaries. If confirmed malicious, this behavior could allow attackers to execute code remotely, escalate privileges, or persist within the environment.


• Ivanti Connect Secure System Information Access via Auth Bypass :
  network VPN Appliance risk_score:72 2024-09-30 version:3
  The following analytic identifies attempts to exploit the CVE-2023-46805 and CVE-2024-21887 vulnerabilities in Ivanti Connect Secure. It detects GET requests to the /api/v1/totp/user-backup-code/../../system/system-information URI, which leverage an authentication bypass to access system information. The detection uses the Web datamodel to identify requests with a 200 OK response, indicating a successful exploit attempt. This activity is significant as it reveals potential unauthorized access to sensitive system information. If confirmed malicious, attackers could gain critical insights into the system, facilitating further exploitation and compromise.


• Scheduled Task Deleted Or Created via CMD :
  endpoint Endpoint risk_score:56 2024-09-30 version:8
  The following analytic identifies the creation or deletion of scheduled tasks using the schtasks.exe utility with the -create or -delete flags. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line executions. This activity is significant as it can indicate unauthorized system manipulation or malicious intent, often associated with threat actors like Dragonfly and incidents such as the SUNBURST attack. If confirmed malicious, this activity could allow attackers to execute code, escalate privileges, or persist within the environment, posing a significant security risk.


• PowerShell 4104 Hunting :
  endpoint Endpoint risk_score:80 2024-12-11 version:8
  The following analytic identifies suspicious PowerShell execution using Script Block Logging (EventCode 4104). It leverages specific patterns and keywords within the ScriptBlockText field to detect potentially malicious activities. This detection is significant for SOC analysts as PowerShell is commonly used by attackers for various malicious purposes, including code execution, privilege escalation, and persistence. If confirmed malicious, this activity could allow attackers to execute arbitrary commands, exfiltrate data, or maintain long-term access to the compromised system, posing a severe threat to the organization's security.


• Windows Identify PowerShell Web Access IIS Pool :
  endpoint Endpoint risk_score:64 2024-10-17 version:2
  This analytic detects and analyzes PowerShell Web Access (PSWA) usage in Windows environments. It tracks both connection attempts (EventID 4648) and successful logons (EventID 4624) associated with PSWA, providing a comprehensive view of access patterns. The analytic identifies PSWA's operational status, host servers, processes, and connection metrics. It highlights unique target accounts, domains accessed, and verifies logon types. This information is crucial for detecting potential misuse, such as lateral movement, brute force attempts, or unusual access patterns. By offering insights into PSWA activity, it enables security teams to quickly assess and investigate potential security incidents involving this powerful administrative tool.


• Windows Ngrok Reverse Proxy Usage :
  endpoint Endpoint risk_score:50 2024-09-30 version:5
  The following analytic detects the execution of ngrok.exe on a Windows operating system. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and command-line arguments. This activity is significant because while ngrok is a legitimate tool for creating secure tunnels, it is increasingly used by adversaries to bypass network defenses and establish reverse proxies. If confirmed malicious, this could allow attackers to exfiltrate data, maintain persistence, or facilitate further attacks by tunneling traffic through the compromised system.


• Windows DISM Install PowerShell Web Access :
  endpoint Endpoint risk_score:72 2024-09-30 version:4
  The following analytic detects the installation of PowerShell Web Access using the Deployment Image Servicing and Management (DISM) tool. It leverages Sysmon EventID 1 to identify the execution of `dism.exe` with specific parameters related to enabling the WindowsPowerShellWebAccess feature. This activity is significant because enabling PowerShell Web Access can facilitate remote execution of PowerShell commands, potentially allowing an attacker to gain unauthorized access to systems and networks. If confirmed malicious, this action could lead to further exploitation and compromise of the affected system.


• Detect Remote Access Software Usage Process :
  endpoint Endpoint risk_score:25 2024-09-30 version:4
  The following analytic detects the execution of known remote access software within the environment. It leverages data from Endpoint Detection and Response (EDR) agents, focusing on process names and parent processes mapped to the Endpoint data model. This activity is significant as adversaries often use remote access tools like AnyDesk, GoToMyPC, LogMeIn, and TeamViewer to maintain unauthorized access. If confirmed malicious, this could allow attackers to control systems remotely, exfiltrate data, or deploy additional malware, posing a severe threat to the organization's security.