Advisory

A note with CVSS 4.7 for component BC-FES-ITS was released by SAP on 09.02.2021. The correction/advisory 2973428 was described with "Reverse Tabnabbing vulnerability within SAP NetWeaver Application Server ABAP (Applications based on SAP GUI for HTML)" and affects the system type Kernel.

A workaround does not exist, according to SAP Security Advisory team. It is advisable to implement the correction as monthly patch process.

The vulnerability addressed is reverse tabnabbing within Kernel.

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:

Reverse Tabnabbing Overview — Source: OWASP.org

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 specification

SAP GUI for HTML allows an unauthenticated remote attacker to redirect users to a malicious site due to insufficient reverse tabnabbing URL validation.

Solution

The solution impacts the method 'cl_gui_html_viewer'. Therefore, to resolve the issue the most current SAPEXE SAR for your kernel needs to be installed.

The advisory is valid for

Releated advisories

Disclaimer

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The advisories found within the SecurityBridge advisory are generated and continuously enriched by our Team at SecurityBridge and affiliated security consultants, partners, customers of the SecurityBridge Platform, SAP support, and advisory groups.

We do not disclose zero-day vulnerabilities unless a security patch has been made available to the public. In such case, the platform only provides details on which version or signature updates are available within the SecurityBridge platform in order to monitor or measure the vulnerability.

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Notifications

Affected system Kernel

CVSS 4.7

Component BC-FES-ITS

Patch Day2021-02

Released on2021/02/09

SAP Note 2973428

Workaround No

Advisory

Risk specification

Solution

Disclaimer

_{Affected system}
Kernel

_CVSS
4.7

_Component
BC-FES-ITS

_{Patch Day}
2021-02

_{Released
on}
2021/02/09

_{SAP Note}
2973428

_Workaround
No