Advisory
On 12.05.2020 a security relevant correction has been released by SAP SE. The manufacturer resolves an issue within ABAP.
SAP Note 2747062 addresses "This note has been re-released without changes. - Cross-Site Request Forgery (CSRF) vulnerability in SAP Web Dynpro ABAP" to prevent cross-site request forgery (xsrf) with a medium risk for exploitation.
A workaround does not exist, according to SAP Security Advisory team. It is advisable to implement the correction as monthly patch process, 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 specification
This note has been re-released with updated ‘Correction instructions’ information.Web Dynpro ABAP allows an attacker to trick an authenticated user to send unintended requests to the web server.Solution
The tracing from the origin session is changed in a way that as long no token is provided with the request and as long only automatic requests (like loading placeholder request) reaches the backend that data are buffered till the first "click" request of user is recognized. In a second session the possibility to add comments and files is removed.
Affected System
The advisory 2747062 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
- SAP_UI 750 18
- SAP_UI 751 4
- SAP_UI 752 8
- SAP_UI 753 18
- SAP_BASIS 700-702 66
- SAP_BASIS 710-711 21
- SAP_BASIS 730 34
- SAP_BASIS 731 78
- SAP_BASIS 804 10
- SAP_BASIS 776
- 9.9 [CVE-2021-33690] Server Side Request Forgery vulnerability in SAP NetWeaver Development Infrastructure (Component Build Service)
- 7.6 [CVE-2020-6275] Server Side Request Forgery vulnerability in SAP NetWeaver AS ABAP
- 6.3 Cross-Site Request Forgery (CSRF) vulnerability in multiple SAP Sybase products
- 5.5 Cross-Site Request Forgery (CSRF) vulnerability in Cash Management
- 5.4 Cross-Site Request Forgery (CSRF) vulnerability in S/4HANA Finance for advanced payment management
