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 AS Java Home: SAP Netweaver Application Server Java wiki
A dedicated SAP NetWeaver 7.40 Application Server for Java Security Guide exists.

The advisory is valid for

Releated advisories

Disclaimer

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Notifications

Affected system Java

CVSS 10.0

Component BC-JAS-COR-CLS

Patch Day2020-12

Released on2020/12/08

SAP Note 2974774

Workaround Yes

Advisory

Risk specification

Solution

Affected System

Disclaimer

_{Affected system}
Java

_CVSS
10.0

_Component
BC-JAS-COR-CLS

_{Patch Day}
2020-12

_{Released
on}
2020/12/08

_{SAP Note}
2974774

_Workaround
Yes