A note with CVSS 6.5 for component BC-SRV-PMI was released by SAP on 13.04.2021. The correction/advisory 3028729 was described with "[CVE-2021-27603] Denial of Service (DoS) in SAP NetWeaver AS of ABAP" and affects the system type ABAP.
A workaround does not exist, according to SAP Security Advisory team. It is advisable to implement the correction as monthly patch process .
The vulnerability addressed is denial of service (dos) within ABAP.
Missing authority checks are still the most common security defect related to authorizations in custom code. Since SAP uses an explicit authorization model, an authority checks must be coded in order to be executed. If an explicit check is not coded, all users have access. This type of vulnerability not only exists in SAP standard it also exists in customer coding. Check your custom developments for vulnerabilities that pose a risk to your systems. SecurityBridge helps detect code vulnerabilities before they are implemented in production. Denial of Service (DoS) attacks that take a system offline may lead to significant cost for the company, studies quantify the costs in average between 4 and 5 millions dollars. Business continuity requires SAP systems staying online. The CVSS scores or vulnerability descriptions are not enough to represent how a simple bug can lead to a significant loss for companies.
Risk specificationAn RFC-enabled function module SPI_WAIT_MILLIS in SAP NetWeaver AS ABAP allows an attacker to keep a work process busy for any length of time. The attacker could call this function module multiple times to block all work processes resulting in Denial of Service.
The respective function module is changed so that no code can be executed anymore which causes a delayed response.
The advisory 3028729 describes a problem within an ABAP based systems of a specific version. Affected versions are described below. ABAP software is deployed in various software components and is widely used within the SAP product portfolio.
SAP NetWeaver Application Server (formally known as SAP Web Application Server) is a building block of SAP NetWeaver. It is the foundation for most software products developed by SAP SE. SAP NetWeaver systems exist with Java and/or ABAP stacks. The advisory could be relevant for single and dual-stack ABAP installations.
The advisory is valid for
- 9.8 Multiple Vulnerabilities in SAP Data Services
- 7.5 [CVE-2021-38177] Null Pointer Dereference vulnerability in SAP CommonCryptoLib
- 6.5 [CVE-2020-26826] Unrestricted File Upload vulnerability in SAP NetWeaver Application Server for Java (Process Integration Monitoring)
- 6.5 [CVE-2021-21488] Insecure deserialisation in SAP NetWeaver Knowledge Management
- 5.9 [Multiple CVEs] Memory Corruption vulnerability in SAP Internet Graphics Service