SAP Netweaver JAVAHigh

Denial of Service in SAP NetWeaver JAVA

Impact On Business

This vulnerability can be used by an attacker to make a Denial of Service to SAP Netweaver Java, making HTTP server unavailable during attack execution.

Affected Components Description

One of the principal entry points in all SAP Application Server Java is the HTTP Web Server. As part of this service there are many standard components analyzing and preprocessing the data sent to and received from the users. Because these components are in a critical place, vulnerabilities on them are really serious and affect all NetWeaver JAVA based SAP Products.

Vulnerability Details

SAP Netweaver Java has a stack of standard J2EE filters responsable to do some controls and statistical operations over each received request. The vulnerability exists because one of those filters is keeping information about the different HTTP methods received by the server, but it is not properly controlling how much memory it needs to store that information. After sending a specially crafted request, an attacker is able to make that filter raise an OutOfMemoryError, making the virtual machine crash.

Solution

SAP has released SAP Note 3056652 which provides patched versions of the affected components.

The patches can be downloaded from https://launchpad.support.sap.com/#/notes/3056652

Onapsis strongly recommends SAP customers to download the related security fixes and apply them to the affected components in order to reduce business risks.

Report Timeline

  • 04-26-2021 – Onapsis provides details to SAP
  • 04-29-2021 – SAP Provides a tracking number
  • 05-10-2021 – SAP provides update: Vulnerability being fixed
  • 07-12-2021 – SAP release patch #3056652
  • 05-04-2022 – Advisory Published

REFERENCES

Advisory Information

  • Public Release Date: 04/05/2022
  • Security Advisory ID: ONAPSIS-2022-0002
  • Vulnerability Submission ID: 882
  • Researcher(s): Gaston Traberg

Vulnerability Information

  • Vendor: SAP
  • Vulnerability Class: |LS|CWE-400|RS| Uncontrolled Resource Consumption
  • CVSS v3 score: 7.5 V:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
  • Severity: High
  • CVE: CVE-2021-33670
  • Vendor patch Information: SAP Security Note 3056652

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