Advisory

A note with CVSS 8.8 for component KM-KW-HTA was released by SAP on 14.12.2021. The correction/advisory 3102769 was described with "[CVE-2021-42063] Cross-Site Scripting (XSS) vulnerability in SAP Knowledge Warehouse" and affects the system type Java.

A workaround exists, according to SAP Security Advisory team. It is advisable to implement the correction as monthly patch process.

The vulnerability addressed is Cross-Site Scripting (XSS) within Java.

Cross-site scripting (XSS) is the name of a class of security vulnerabilities that can occur in web-based applications. XSS combines all vulnerabilities that allow an attacker to inject HTML Markup and/or JavaScript into the front end of the affected web application.

XSS attacks can occur whenever the application dynamically creates its HTML/JavaScript/CSS content, which is passed to the user's web browser, and attacker-controlled values are used in this process. If these values are included in the generated code without proper validation and encoding, the attacker is able to include arbitrary coding snippets into the application's front end. The code is then rendered by the victim's web browser and interpreted in the victim's current authentication context.

Risk specification

SAP Knowledge Warehouse does not sufficiently encode user controlled inputs, resulting in Cross-Site Scripting (XSS) vulnerability.

Solution

The user input is now properly encoded to prevent a successful XSS attack. Although an alternative solution exists, it is advisable to apply the correction! This is the workaround, which was suggested by the SAP security experts: "Option 1: You may disable the vulnerable application following the documentation in "Config Tool Adding Filters - SAP Help Portal" (https://help.sap.com/viewer/0c333adb55cd4dbf8e92a5175703224c/7.5.19/en-US/47b1a4e5ac671599e10000000a42189c.html). 'Component Name Mask' parameter should be set as tc~km_tc*, 'Vendor Mask' Parameter - sap.com. Option 2: In case the requests are routed via SAP Web Dispatcher you may add a rewrite rule to SAP Web Dispatcher to prevent from redirects. Add the following rewrite rule to your Web Dispatcher configuration. RegIForbiddenUrl ^/path/of/java/app.* -If there is an existing icm/HTTP/mod_<x> = PREFIX=/, FILE=<...> in your setup: Add the new rule (above) to your existing rule file. Restart the Web Dispatcher or reload the file using the Web Administration UI. Otherwise: Create a new file on the file system (for example in the profile directory) and enter the role above in that file.Add a new parameter icm/HTTP/mod_0 = PREFIX=/, FILE=<your created file>. Do not forget to restart the Web Dispatcher. ".

Affected System

SAP Netweaver Application Server Java is part of the SAP NetWeaver Application Platform. It provides the complete infrastructure for deploying and running Java applications.

The AS Java Home: SAP Netweaver Application Server Java wiki
A dedicated SAP NetWeaver 7.40 Application Server for Java Security Guide exists.

The advisory is valid for

KM-KW_JIKS 7.30
KM-KW_JIKS 7.31
KM-KW_JIKS 7.40
KM-KW_JIKS 7.50

Releated advisories

Disclaimer

SecurityBridge takes the security of SAP products very seriously. We very much encourage the responsible disclosure of security vulnerabilities. If you have detected a vulnerability concerning one of the SAP software products – either in the latest or in a former product version follow the guidelines and processes in accordance with the SAP portal page “Report a Security Vulnerability to SAP”.

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.

In accordance with SAP guidelines, SecurityBridge only discloses issues where the fixing security note has been released. The vulnerability platform makes no references to available exploits or Proof of Concepts (PoC). Advisories and vulnerabilities will always mention the fixing security note or hints to the corresponding SAP documentation.

SecurityBridge - Smart connector SAP to SIEM

SmartConnector ^{SAP© to SIEM}
Enable your global monitoring to detect malicious action in SAP systems to protect your company against Cross-Site Scripting (XSS) or Denial of service (DoS) attacks.

Follow @_securitybridge

Notifications

Affected system Java

CVSS 8.8

Component KM-KW-HTA

Patch Day2021-12

Released on2021/12/14

SAP Note 3102769

Workaround Yes

Advisory

Risk specification

Solution

Affected System

Disclaimer

_{Affected system}
Java

_CVSS
8.8

_Component
KM-KW-HTA

_{Patch Day}
2021-12

_{Released
on}
2021/12/14

_{SAP Note}
3102769

_Workaround
Yes