CVE-2021-27621 Explained : Impact and Mitigation

A detailed overview of the Information Disclosure vulnerability in the UserAdmin application of SAP NetWeaver AS for Java, versions 7.11, 7.20, 7.30, 7.31, 7.40, and 7.50, allowing unauthorized access to restricted information by exploiting a malicious server name.

Understanding CVE-2021-27621

This section delves into the impact, technical details, and mitigation strategies related to the Information Disclosure vulnerability designated as CVE-2021-27621.

What is CVE-2021-27621?

The CVE-2021-27621 vulnerability targets the UserAdmin component of SAP NetWeaver AS for Java, enabling threat actors to obtain sensitive data by manipulating server names maliciously.

The Impact of CVE-2021-27621

The flaw poses a medium-severity risk with a CVSS base score of 5.5 due to unauthorized disclosure of low-impact confidential and integrity information. Attackers can exploit this vulnerability over a network with high privileges required.

Technical Details of CVE-2021-27621

This section covers the specific attributes concerning the vulnerability, including the vulnerability description, affected systems, and the exploitation mechanism.

Vulnerability Description

The Information Disclosure vulnerability in the UserAdmin application of SAP NetWeaver AS for Java version < 7.50 permits threat actors to access confidential information through the input of a crafted server name.

Affected Systems and Versions

SAP NetWeaver AS for Java versions 7.11, 7.20, 7.30, 7.31, 7.40, and < 7.50 are susceptible to this vulnerability, potentially compromising the confidentiality and integrity of user data.

Exploitation Mechanism

By manipulating the server name input, attackers can bypass restrictions and extract sensitive information, exploiting the flaw with a low attack complexity and no user interaction requirement.

Mitigation and Prevention

The following section outlines crucial steps to address and prevent the CVE-2021-27621 vulnerability, safeguarding systems against potential exploitation.

Immediate Steps to Take

It is essential to apply the relevant patches provided by SAP to mitigate the vulnerability effectively. Ensure that systems running the affected versions are promptly updated to prevent unauthorized data access.

Long-Term Security Practices

In addition to patching, maintaining robust access controls, conducting regular security audits, and fostering user awareness can enhance the overall security posture of SAP NetWeaver AS for Java instances.

Patching and Updates

Regularly monitor SAP security advisories and apply security patches in a timely manner to address known vulnerabilities and strengthen the defense mechanisms of the affected systems.