SAP takes the security of its vast product portfolio very seriously and thus releases security fixes for
vulnerabilities reported by external researchers and their customers every second Tuesday of the month.
SAP Note 3068337
was released on
14.09.2021 and deals with
"Reverse tabnabbing vulnerability in SAP Marketing Lead Nurture Stream" within ABAP.
We advice you to follow the instructions, to resolve
low potential for exploitation
in component CEC-MKT-CPG-LNS.
According to SAP Security Advisory team a workaround does not exist. It is advisable to implement the correction as monthly patch process.
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
vulnerabilities before they are implemented in production.
Reverse tabnabbing is an attack where a page linked from the target page is able to rewrite that page, for example
to replace it with a phishing site. The following figure shows a brief illustration:
While the user was originally on the correct page there is a high risk they will not notice that it has been changed to a phishing site.
Risk specificationSAP Marketing Lead Nurture Stream allows an authenticated attacker to exploit a reverse tabnabbing vulnerability in which a link on the page is able to rewrite that page. This may result in phishing attacks on user credentials or redirects user to malicious web pages.
Only certain properties are allowed to be shared between parent and client pages.
The advisory 3068337 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
- 4.7 [CVE-2021-21491] Reverse TabNabbing vulnerability in SAP NetWeaver Application Server Java (Applications based on Web Dynpro Java)
- 4.7 Reverse Tabnabbing vulnerability within SAP NetWeaver Application Server ABAP (Applications based on SAP GUI for HTML)
- 4.7 [CVE-2021-33697] Reverse Tabnabbing in SAP BusinessObjects Business Intelligence Platform (SAP UI5)
- 4.7 [CVE-2021-21478] Reverse Tabnabbing vulnerability in SAP NetWeaver Application Server ABAP (Applications based on Web Dynpro ABAP)
- 4.7 Reverse TabNabbing vulnerability in SAP NetWeaver Application Server Java (Applications based on HTMLB for Java)