On 12.03.2019 a security relevant correction has been released by SAP SE. The manufacturer resolves an issue within ABAP.
SAP Note 2531082 addresses "Switchable Authorization checks for RFC BCA_DIM_LOANS_APPLOG_UPDATE in Loans (FI-CAX-FS)" to prevent missing authorization check with a medium risk for exploitation.
A workaround does exist, according to SAP Security Advisory team. It is advisable to implement the correction as project***, the team suggests.
Missing authority checks are still the most common security defect related to authorizations in custom code. Since SAP uses an explicit authorization model, an authority checks must be coded in order to be executed. If an explicit check is not coded, all users have access. This type of vulnerability not only exists in SAP standard it also exists in customer coding. Check your custom developments for vulnerabilities that pose a risk to your systems. SecurityBridge helps detect code vulnerabilities before they are implemented in production.
Risk specificationAn authenticated attacker can execute business functions via a remote function call on BCA_LOANS_APPLOG_UPDATE (Update Application log for Loans RFCs) without being properly authorized due to missing or insufficient authorization check.
Additional authorization checks are introduced via the Switchable Authorization Framework (SACF) for new authorization object S_RFC for Scenario FS_TB_APPL_LOG. And the good news are: a workaround exists, too! This was suggested by the SAP security experts: "Maintain strict governance on object S_RFC (no the wildcard '*' in function groups or names) in all user roles. Alternatively, implement UCON and switch off remote capability of unused function modules."
The advisory 2531082 describes a problem within an ABAP based systems of a specific version. Affected versions are described below. ABAP software is deployed in various software components and is widely used within the SAP product portfolio.
SAP NetWeaver Application Server (formally known as SAP Web Application Server) is a building block of SAP NetWeaver. It is the foundation for most software products developed by SAP SE. SAP NetWeaver systems exist with Java and/or ABAP stacks. The advisory could be relevant for single and dual-stack ABAP installations.
The advisory is valid for
- FI-CAX 602 2
- FI-CAX 603 2
- FI-CAX 604 2
- FI-CAX 605 2
- FI-CAX 606 2
- FI-CAX 616 2
- FI-CAX 617 2
- FI-CAX 618 2
- FI-CAX 619
- FI-CAX 800 2
- FI-CAX 801 2
- FI-CAX 802 2
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