Advisory

On 08.12.2020 a security relevant correction has been released by SAP SE. The manufacturer resolves an issue within Java.

SAP Note 2974774 addresses "[CVE-2020-26829] Missing Authentication Check in SAP NetWeaver AS JAVA (P2P Cluster Communication)" to prevent missing authentication check with a hot news risk for exploitation.

A workaround does exist, according to SAP Security Advisory team. It is advisable to implement the correction as part of maintenance, the team suggests.

Risk specification

An unauthenticated attacker can invoke certain functions that would otherwise be restricted to system administrators only, including access to system administration functions or shutting down the system completely.

Solution

The Server Socket for P2P communication now listens only on the network interface dedicated to internal cluster communication. Extra security measures have been introduced in the P2P handshake protocol so that if attackers gain access to the network segment dedicated to the AS Java Cluster, they cannot establish a connection to the P2P Server Socket of any server nodes in the Cluster.  Circumstances exist that prevent the timely installation of a patch provided by the manufacturer. In such cases, you may consider applying the suggested workaround as a temporary or compensating mitigation: "Configure Message Server ACL to allow P2P connections only from trusted IP addresses according to the documentation: Security Settings for the SAP Message Server. Make sure that the Join Port, opened by the P2P Server Socket, is protected on network level via network segmentation, with firewall, or both. Furthermore, the communication between the cluster elements has to be secured via the IPsec protocol suite.".

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 advisory is valid for

 

Disclaimer

ABEX takes the security of SAP products very seriously. We very much encourage the responsible disclosure of security vulnerabilities. If you have detected a vulnerability in 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 ABEX security advisory are generated and continuously enriched by ABEX and affiliated security consultants, partners, customers of the SecurityBridge security suite, SAP support, and advisory groups.

There is no disclosure of zero-day vulnerabilities. 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, ABEX only discloses issues where the fixing security note has been released at least three months ago. 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.

 

Follow us:

 

SecurityBridge

SecurityBridgefor SAP©
empowers security teams with forward-looking, high fidelity, adversary-focused intelligence and actionable events from SAP Netweaver based systems.