Layer Seven, Author at Layer Seven Security

SAP Security Notes, August 2019

Layer Seven on September 5, 2019

Hot News Note 2800779 patches a remote code execution vulnerability in the SAP NetWeaver UDDI Server. The vulnerability carries a CVSS score of 9.9/10 and could be exploited to take complete control of the Services Registry, including viewing, changing, or deleting data by injecting code into the working memory which is subsequently executed by the application. The NetWeaver UDDI Server is an XML-based registry for Web Services.

Note 2786035 patches another critical remote code execution vulnerability in SAP Commerce Cloud (previously SAP Hybris Commerce). The Mediaconversion and Virtualjdbc extensions in SAP Commerce Cloud could execute malicious code injected by attackers or authenticated users. Note that some of the Mediaconversion Conversion Command parameters may not work after the implementation of the recommended patch until they are added to a whitelist.

Note 2813811 deals with a dangerous Server-Side Request Forgery (SSRF) vulnerability in the Administrator System Overview of SAP NetWeaver Application Server for Java (AS Java). The vulnerability could enable attackers to scan internal networks, perform Remote File Inclusion attacks, retrieve server files including password files, bypass firewalls, and force vulnerable servers to execute malicious requests. Refer to SAP KBA 2577844 to resolve known side-effects of the corrections in Note 2813811.

SAP Security Notes, July 2019

Layer Seven on August 14, 2019

Hot News Note 2808158 patches a critical code injection vulnerability in the SAP Diagnostics Agent. The Agent is required to monitor operating systems and discover the database cluster topology from SAP Solution Manager. It is not required for monitoring the security of SAP systems with Solution Manager. Security-relevant data is collected or monitored primarily through RFC connections maintained between Solution Manager and managed systems.

The vulnerability impacts the OS Command Plugin in transaction GPA_ADMIN. The transaction is used to create and maintain guided procedures. Note 2808158 provides a patch for the LM_SERVICE in SP levels 05-09 of Solution Manager 7.2.

Note 2774489 addresses a high priority OS command injection vulnerability in SAP Process Integration (PI). ABAP Tests Modules of PI could enable attackers to execute privileged OS commands. The relevant support packages listed in the note should be applied to remove the vulnerable source code in the modules.

Monitoring Security Alerts with SAP Solution Manager

Layer Seven on August 14, 2019

There are several apps available in SAP Solution Manager for monitoring security alerts for SAP systems. The most longstanding is the Alert Inbox which provides an overview of alerts by process area. Guided procedures for investigating security alerts are executed from the Alert Inbox. Another option is System Monitoring which provides a more user-friendly interface for navigating incidents than the Alert Inbox. System Monitoring includes the Alert Ticker displayed in the right pane of the app for monitoring incidents in real-time.

SAP Solution Manager 7.2 SP07 introduced a third option for monitoring alerts called Monitor Systems. The app is delivered in the new work center Application Operations.

System Monitoring and the Alert Inbox are Web Dynpro applications. Monitor Systems, however, is a SAPUI5 application based on the Fiori framework. Therefore, Monitor Systems delivers exceptional performance with alerts loading and refreshing at much faster rates than both the Alert Inbox and System Monitoring. The performance gains are considerable even for SAP Solution Manager installations running on conventional databases rather than SAP HANA.

You can access Monitor Systems from the SAP Fiori Launchpad using the roles SAP_STUI_APPOPS_AUTH and SAP_STUI_APPOPS_TCR.

The initial screen summarizes alerts open alerts by systems and components.

Alerts are categorized by the groups below. Security alerts triggered by the Cybersecurity Extension for SAP Solution Manager are categorized in the Configuration and Exception classes.

Results can be filtered or sorted by clicking by system and category.

Systems can also be labeled as favorites for fast selection.

You can view details of open alerts for each system by clicking on the system. Below are alerts for security configuration issues impacting system AS2.

Below are security exceptions detected through real-time monitoring of event logs in the system.

We can drill down into the details of each alert by clicking on Critical Metrics. For example, we can investigate the alert below for the Actions by the Standard SAP* User Alert by reviewing the relevant metric.

The Metric Details reveals that there was an attempted logon with the SAP* user from IP address 10.8.91.2 at 12:51 on 2019-08-14. We can execute a guided procedure that will investigate other actions from the source IP directly in the Security Audit Log.

The results can be shared with security operations teams through email by clicking on the Notify option in the Metric Details.

In another example, we can drill down into the alert for active users logged into the system with SAP_ALL in their user buffer to investigate potential privilege escalation. The profile should not be used in productive systems.

Recommended Settings for SAP Logging and Auditing

Layer Seven on July 25, 2019

The Cybersecurity Extension for SAP Solution Manager monitors SAP event logs to automatically detect and alert for indicators of compromise. The monitoring interval can be customized for each security metric based on risk and sizing. An interval of 60 seconds, for example, can support real-time threat detection. However, real-time detection is only useful when supported by real-time incident response. Organizations that lack rapid response capabilities should opt for collection intervals of 10-15 minutes to balance the need to minimize the mean to detect (MTTD) with the system impact of continuous monitoring.

Log settings also need to be carefully maintained to capture security-relevant events while preventing the accumulation of log data and the consumption of excessive disk or table space. The recommended settings and archiving procedures below for each log area will enable you to maintain comprehensive forensic logs with minimal system impact.

Security Audit Log
Maintain static filters to log all actions by the standard SAP* user, logons and transaction starts by the DDIC user, and Severe and Critical events for all audit classes and users. Also create a static filter to log the non-critical event IDs BU4, CUY, DU9, DUI, and FU1. The filters should be applied to all clients. If you have yet to remove the EarlyWatch client, also create a filter to monitor events for all audit classes and users in client 066.

Periodically export events older than 30 days using transaction SM20. Once the events are successfully exported and backed-up to a file server, trigger the background job RSAUPURG to delete events older than 30 days using transaction SM18.

Read Access Log
Configure or import logging purposes to log access to sensitive fields and tables including user tables. Archive SRAL objects using transaction SARA. RAL archives can exported and stored offline.

Change Documents
Change documents for user changes are triggered automatically. Similar to the Read Access Log, change documents are archived using transaction SARA.

Business Transaction Log
There are no specific settings required for STAD. Since data is retained for only 48 hours, STAD archiving is also not required.

System Log
Similarly, the system log does not require any specific settings or archiving. The system log is a ring buffer. When the log file reaches its maximum size, the system overwrites the oldest data.

HTTP Log
The LOGFORMAT option for HTTP logging should specify a format that includes the URL in log entries. An example is the CLF format. HTTP log files in the /usr/sap/SID/instance/work directory can be exported and archived offline.

Gateway Server
The ACTION option for gateway logging should include the actions SsZMP to capture security events, configuration changes, and monitor commands. Gateway log files are can also be found in the work directory of each instance and archived to an external location.

Java Security Log
The value of the following properties should be set to TRUE to include the client host address, object name and actor in logged events: ume.logon.security_policy.log_client_hostaddress, ume.secaudit.get_object_name, and ume.secaudit.log_actor. Automatic archiving should be activated using the Log Manager. Once activated, the compressed archives can be found in usr\sap\<SID>\JC<Instance number>\j2ee\cluster\<Dispatcher or server>\log\archive.

HANA Audit Log
The target audit trails should be set to CSTABLE and SYSLOGPROTOCOL to log events simultaneously to internal tables and the OS-level system log. Audit policies should be configured to log critical actions including all actions performed by the SYSTEM user, system changes, user changes, role changes, repository changes, and unsuccessful logons.

The contents of the AUDIT_LOG table can be exported using the AUDIT OPERATOR privilege in the HANA Studio. Once exported, navigate to the Auditing tab in the Security section and select the option to truncate the audit trail.

For detailed step-by-step instructions, refer to the section on Log Settings and Maintenance in the user manual for the Cybersecurity Extension for SAP Solution Manager.

SAP Security Notes, June 2019

Layer Seven on July 5, 2019

Note 2748699 provides instructions for securing the credentials of the standard user SM_EXTERN_WS in SAP Solution Manager. SM_EXTERN_WS is used by CA Introscope Enterprise Manager (EM) to collect monitoring metrics from mainly non-ABAP components in SAP landscapes. The metrics are collected via the Introscope Push web service. The credentials for SM_EXTERN_WS including the automatically generated password are stored in a file that is referenced with property dpcpush.credentials.file in file <EM_install_dir>/sap/<SolMan_SID>.e2emai.properties. The credentials in the file are insufficiently protected against attackers. However, dialog logon with SM_EXTERN_WS is not possible since the user is a system user type. Also, SM_EXTERN_WS does not have administrative privileges.

Note 2748699 recommends deploying the LM-SERVICE software component and patching the Management Module for Enterprise Manager. Also, it includes instructions for enabling encryption to protect the password file.

Switchable authorization checks were introduced by notes 2524203, 2527346 and 2496977 to supplement checks performed using authorization object S_RFC for critical Remote-enabled Function Modules (RFMs) in components of SAP ERP. This includes RFMs in Accounts Receivable and Payable, Materials Management, and Sales and Distribution.

Webinar Playback: Holistic SAP Cybersecurity with CVA & SolMan

Layer Seven on June 20, 2019

Watch the pla yback of this month’s webinar to learn how you can implement holistic cybersecurity for your SAP systems with Code Vulnerability Analyzer and Solution Manager.

CVA performs static code analysis to detect vulnerabilities in custom code. SAP Solution Manager detects vulnerabilities and threats in SAP systems including components such as the gateway server, message server and SAProuter, targeted by the recent 10KBLAZE exploits.

Together, CVA and Solution Manager provide an integrated platform to secure custom code and SAP systems against cyber threats.

SAP Security Notes, May 2019

Layer Seven on June 7, 2019

Note 1408081 was updated in May in response to the recent 10KBLAZE exploits targeting vulnerabilities in the gateway server. The note includes revised instructions for maintaining access control lists in the gateway security files reg_info and sec_info for different kernel versions. The access control lists should be configured to control external server registrations and program starts. The note recommends restricting registrations and starts to within the same system or SID cluster using the options ‘local’ and ‘internal’. However, the updates do not mention the risk that the security mechanisms applied by the recommended entries could be bypassed by attackers that register as internal servers with the message server. Therefore, it is critical to maintain access control lists for the message server to support the secure configuration of the gateway server.

For additional security against 10KBLAZE exploits, a separate port should be configured for internal message server communications, external monitor commands should be rejected, communications between kernel components should be encrypted, and the bit mask value for the profile parameter gw/reg_no_con_info should be set to a value of 255.

Note 2756453 provides manual instructions and automated corrections for removing a high-risk cross-site scripting vulnerability in S/4HANA.

Note 2784307 deals with another high-risk vulnerability in the REST Interface that could be exploited to escalate privileges in SAP Identity Management.

10KBLAZE: Secure Your Systems with SAP Solution Manager

Layer Seven on May 13, 2019

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.

Webinar: 10KBLAZE – Secure Your SAP Systems with CVA and SolMan

Layer Seven on May 9, 2019

According to a recent report, thousands of SAP installations may be vulnerable to 10KBLAZE exploits targeting SAP applications.

Join SAP and Layer Seven Security to learn how to secure your SAP systems against the exploits with SAP Code Vulnerability Analyzer (CVA) and SAP Solution Manager. CVA performs static code analysis to detect vulnerabilities in custom code. SAP Solution Manager detects vulnerabilities and threats in SAP systems including components such as the gateway server, message server and SAProuter, targeted by 10KBLAZE.

Together, CVA and Solution Manager provide an integrated platform to secure your business-critical SAP systems against 10KBLAZE and other exploits.

Thu, Jun 6, 2019
11:00 AM – 12:00 PM EDT

SAP Security Notes, April 2019

Layer Seven on May 7, 2019

Note 2747683 patches a vulnerability in the signature security mechanism of the Adapter Engine in SAP NetWeaver Process Integration (PI). The vulnerability could enable attackers to spoof XML signatures and send arbitrary requests to the server via PI Axis adapter. Such requests will be accepted by the PI Axis adapter even if the payload has been altered, especially when the signed element is the body of the xml document. SAP has corrected the relevant code in PI Axis Adapter. The corrections apply additional checks for signed elements for correctness before signature validation. Customers should apply the relevant support packages and patches referenced by SAP Note 2747683.

Note 2776558 provides corrections for a high-risk insufficient authorization check in SAP Funding Management. The vulnerability could be exploited to escalate privileges and carries a CVSS score of 8.3/10.

Notes 2742758 and 2741201 deal with information disclosure vulnerabilities in in the messaging system and runtime workbench of SAP PI. This could lead to the leakage of sensitive system information that could be exploited to perform further attacks against the platform.

Note 2687663 patches a similar vulnerability in the .NET SDK WebForm Viewer of SAP Crystal Reports. Sensitive database information that could be disclosed by exploiting the vulnerability include user credentials.