Category: SAP Audit

On May 2, the Department of Homeland Security issued an alert for SAP customers in response to the disclosure of new exploits targeting vulnerable SAP components. According to some reports, the so-called 10KBLAZE exploits could impact 90% of SAP installations worldwide. The exploits target misconfigurations in the gateway server and message server installed in most SAP systems including S/4HANA, ERP and CRM. The successful execution of the exploits could enable attackers to exfiltrate or modify data and provoke a denial of service without authentication. In other words, attackers can completely compromise target SAP systems without any user credentials.

The new exploits target known vulnerabilities addressed by notes and advisories released by SAP since 2005.  Note 821875 details measures to secure the message server, including restricting external access, separating internal and external communications, and maintaining secure access control lists. The profile parameter ms/monitor should be set to 0 to prevent external programs such as msmon from administering the message server at the operating system level. Access to transaction SMMS should also be restricted since the setting can be changed dynamically using the Message Server Monitor within the application server. A separate port for internal communication between application servers should be defined using parameter rdisp/msserv_internal. This will prevent external clients from intercepting or rerouting internal message server communications.  The port should not be exposed to clients or intranets. Finally, the parameter ms/acl_info should specify the file containing a restrictive access control list of hosts, domains, IP addresses or subnets for application servers permitted to log on with the message server.

ACLs should also be defined for the gateway server to control access to starting external programs.  This can be performed using the gateway security file sec_info. The correct syntax for the file depends on the kernel level. For kernel 7.20 and higher, the setting USER-HOST=LOCAL is recommended to protect against 10KBLAZE exploits. This will allow connections from the same server instance. The setting USER-HOST=INTERNAL could be vulnerable but is required for SID clusters. For detailed guidance, refer to Note 1408081. The ACLs should be supported by the setting gw/acl_mode to 1. This parameter defines the behavior of the gateway server if sec_info does not exist.

Since some 10KBLAZE exploits are targeted at modifying or redirecting data packets, enabling SNC to authenticate and encrypt client-server communications is recommended.

SAP systems vulnerable to 10KBLAZE exploits can be discovered using SAP Solution Manager. The Cybersecurity Extension for SAP Solution Manager automatically monitors security settings for the message server and gateway server including profile parameter settings, access control lists and users with critical transactions such as SMMS. The extension also monitors message and gateway logs for external monitor commands, successful and unsuccessful program starts, and other events. Alerts are triggered by the extension for suspected exploits.

The example below illustrates how you can discover insecure sec_info entries that could expose systems to 10KBLAZE exploits.

Click on Vulnerability Report in the Fiori Launchpad.

Filter by ABAP systems, select the check-box for the target system and click on Display.

Filter for vulnerabilities in open status within the area of RFC Security. Click on the check for starting of external programs.

Review the details and recommendation. Click on the linked SAP Notes and SAP Help.

Click on Additional Information to review the insecure entries in the sec_info ACL.

Focus on entries with the setting USER-HOST=internal.

Click on the download icon to export the current settings.

If required, add comments in the Comment section.

The finding for the system will be automatically removed from the report once the sec_info entries are updated. However, you can manually change the status using the Change Status option. Note that status changes are tracked in the extension.

You can also assign responsibility for remediating the finding to specific groups using the Change Owner option.

In response to the dramatic rise of cyber attacks targeting ERP applications, the United States Department of Homeland Security (DHS) issued a warning earlier this year that encouraged organizations to respond to the risks targeted at their business applications by implementing specific measures to secure, patch and monitor SAP systems. The measures included scanning for vulnerabilities and missing security patches, managing SAP interfaces, and monitoring user behaviour, indicators of compromise, and compliance against security baselines for systems.

This article discusses how you can leverage SAP Solution Manager to comply with the DHS recommendations. Solution Manager is installed and available in most SAP landscapes and includes diagnostics and monitoring applications to support cybersecurity. The specific applications are outlined below against each of the DHS recommendations.

1. Scan systems for all known vulnerabilities, such as missing security patches and dangerous system configurations.

Configuration Validation in Solution Manager can perform automatic daily scans of SAP systems against security benchmarks to identify misconfigurations that could expose systems to cyber threats. The scans are performed against snapshots of systems stored in the Configuration and Change Database (CCDB). The results of the scans are stored in an internal Business Warehouse (BW). Service Level Reports and Security Dashboards connect to BW using BEx queries to read the results of the security scans and report the findings.

System Recommendations (SysRec) in Solution Manager connects directly to SAP Support to discover missing security patches.  SysRec also connects to each system in an SAP landscape to determine the current patch level. It reads the system information in the Landscape and Management Database (LMDB) to identify installed software components and versions. SysRec also integrates with the ABAP Call Monitor, Usage Procedure Logging, and Solution Documentation to perform change impact analysis for security patches.

2. Identify and analyze the security settings of SAP interfaces between systems and applications to understand risks posed by these trust relationships.

Interface and Connection Monitoring (ICMon) in Solution Manager automatically maps cross-system interfaces including RFC, HTTP, IDOC and Web Services. This includes internal and external connections. It also monitors real-time traffic patterns to detect and alert for malicious actions including dangerous RFM and URL executions.

3. Analyze systems for malicious or excessive user authorizations.

Solution Manager can detect users with administrative privileges in SAP systems. It flags users with privileged authorizations, profiles, roles, transactions, Java permissions, and HANA system and table privileges. Privileges can include standard and custom objects.

4. Monitor systems for indicators of compromise resulting from the exploitation of vulnerabilities.

The Monitoring and Alerting Infrastructure (MAI) in Solution Manager can monitor event logs in SAP systems to detect and alert for indicators of compromise (IOCs). This includes log files and tables such as the Security Audit Log, HTTP Log, System Log, Gateway Server Log, Change Document Log, Read Access Log, Java Security Log, HANA Audit Log, and the SAProuter Log. The MAI triggers alerts and email and text notifications for IOCs. Guided procedures provide a framework for incident response and tracking.

5. Monitor systems for suspicious user behavior, including both privileged and non-privileged users.

MAI monitors user logs to detect and alert for suspicious behavior covering both privileged and non-privileged users. This includes unauthorized access, escalation of privileges and actions that could lead to data leakage.

6. Apply threat intelligence on new vulnerabilities to improve the security posture against advanced targeted attacks.

SAP Partners periodically update content for Solution Manager to address new vulnerabilities and attack vectors.

7. Define comprehensive security baselines for systems and continuously monitor for compliance violations and remediate detected deviations.

Solution Manager continuously monitors for policy violations against security baselines and compliance frameworks such as GDPR, IT-SOX, NIST and PCI-DSS. Service Level Reports and Dashboards provide directions for implementing and tracking remedial actions taken to patch and secure systems. Guided procedures document incident investigation steps performed by responders. The results are archived in Solution Manager.

To learn more about how Solution Manager can help you comply with the DHS recommendations for securing SAP systems, contact Layer Seven Security.