CVE-2021-27629 : Exploit Details and Defense Strategies

SAP NetWeaver ABAP Server and ABAP Platform (Enqueue Server) versions - KRNL32NUC - 7.22,7.22EXT, KRNL64NUC - 7.22,7.22EXT,7.49, KRNL64UC - 8.04,7.22,7.22EXT,7.49,7.53,7.73, KERNEL - 7.22,8.04,7.49,7.53,7.73, allows an unauthenticated attacker to trigger an internal error in the system and crash it due to improper input validation in method EncPSetUnsupported(), rendering it unavailable.

Understanding CVE-2021-27629

This section provides insights into the impact, technical details, and mitigation strategies related to CVE-2021-27629.

What is CVE-2021-27629?

The vulnerability in SAP NetWeaver ABAP Server and ABAP Platform enables an unauthenticated attacker to crash the system by sending a specially crafted packet over the network.

The Impact of CVE-2021-27629

Exploitation of this vulnerability can lead to a denial of service (DoS) scenario, where the system becomes inaccessible and unavailable for its intended users.

Technical Details of CVE-2021-27629

Here, we delve into the specifics of the vulnerability affecting SAP NetWeaver ABAP Server and ABAP Platform.

Vulnerability Description

The flaw arises from improper input validation in method EncPSetUnsupported() in the affected versions, allowing an attacker to send a malicious packet that triggers an internal error.

Affected Systems and Versions

SAP NetWeaver ABAP Server and ABAP Platform versions - KRNL32NUC - 7.22,7.22EXT, KRNL64NUC - 7.22,7.22EXT,7.49, KRNL64UC - 8.04,7.22,7.22EXT,7.49,7.53,7.73, KERNEL - 7.22,8.04,7.49,7.53,7.73 are impacted by this vulnerability.

Exploitation Mechanism

An unauthenticated attacker can exploit this vulnerability by sending a specially crafted packet over the network, triggering an internal error in the system and causing it to crash.

Mitigation and Prevention

In this section, we outline the steps to mitigate the impact of CVE-2021-27629 and prevent potential security risks.

Immediate Steps to Take

Organizations using the affected versions should apply security patches provided by SAP promptly to address this vulnerability.

Long-Term Security Practices

Implement comprehensive input validation mechanisms and regularly update systems to defend against similar vulnerabilities in the future.

Patching and Updates

Regularly monitor security advisories from SAP and apply recommended patches and updates to ensure system resilience.