CVE-2021-33663 : Security Advisory and Response

SAP NetWeaver AS ABAP, versions - KRNL32NUC - 7.22, 7.22EXT, KRNL32UC - 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, 7.77, 7.81, 7.82, 7.83, 7.84, allows an unauthorized attacker to insert cleartext commands due to improper restriction of I/O buffering into encrypted SMTP sessions over the network which can partially impact the integrity of the application.

Understanding CVE-2021-33663

This section provides insights into the impact, technical details, and mitigation strategies related to CVE-2021-33663.

What is CVE-2021-33663?

CVE-2021-33663 is a vulnerability in SAP NetWeaver AS ABAP that allows unauthorized attackers to insert cleartext commands, compromising the integrity of the application.

The Impact of CVE-2021-33663

The vulnerability can be exploited by attackers to manipulate encrypted SMTP sessions over the network, potentially impacting the application's integrity and security.

Technical Details of CVE-2021-33663

Here are the technical specifics of the CVE-2021-33663 vulnerability:

Vulnerability Description

Improper restriction of I/O buffering leads to the insertion of cleartext commands by unauthorized attackers into encrypted SMTP sessions.

Affected Systems and Versions

SAP NetWeaver AS ABAP versions including KRNL32NUC - 7.22, 7.22EXT, KRNL32UC - 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, 7.77, 7.81, 7.82, 7.83, 7.84 are affected by this vulnerability.

Exploitation Mechanism

The vulnerability allows attackers to insert commands into encrypted SMTP sessions, potentially compromising the confidentiality and integrity of the application.

Mitigation and Prevention

Protect your systems by taking immediate steps and implementing long-term security practices to prevent exploitation of CVE-2021-33663.

Immediate Steps to Take

Ensure encryption mechanisms are correctly implemented, and restrict unnecessary I/O buffering to mitigate the risk of unauthorized command insertion.

Long-Term Security Practices

Regularly monitor and update SAP NetWeaver AS ABAP systems, apply security patches promptly, and conduct security assessments to prevent vulnerabilities.

Patching and Updates

Stay informed about security updates from SAP SE and apply necessary patches to address CVE-2021-33663 effectively.