CVE-2026-23688 is a vulnerability classified under CWE-862 (Missing Authorization) affecting the SAP Fiori App 'Manage Service Entry Sheets - Lean Services' component within SAP S/4HANA Core versions 102 through 107. The flaw arises because the application does not perform necessary authorization checks for authenticated users, allowing them to escalate privileges beyond their assigned roles. This missing authorization means that a user with limited privileges could perform actions or access data reserved for higher privilege levels, compromising the integrity of the system's data or processes. The vulnerability does not impact confidentiality or availability, indicating that sensitive data exposure or denial of service are not concerns here. The CVSS v3.1 base score is 4.3 (medium severity), reflecting that the attack vector is network-based, requires low attack complexity, and requires privileges but no user interaction. No known exploits have been reported in the wild, and SAP has not yet released a patch at the time of this report. The vulnerability affects a critical business process module used for managing service entry sheets, which are essential for verifying and processing external service deliveries in enterprise resource planning (ERP) workflows. The lack of authorization checks could lead to unauthorized modification or creation of service entry sheets, potentially causing financial discrepancies or process manipulation.

For European organizations, this vulnerability poses a risk primarily to the integrity of business processes managed through SAP S/4HANA systems, particularly those using the affected Fiori app for service entry sheet management. Unauthorized privilege escalation could allow malicious insiders or compromised accounts to alter service records, leading to financial inaccuracies, fraud, or disruption of procurement and service management workflows. While confidentiality and availability are not directly impacted, the integrity compromise could have downstream effects on compliance, auditing, and operational reliability. Organizations in sectors with stringent regulatory requirements, such as finance, manufacturing, and public services, may face increased risk of non-compliance or reputational damage if such vulnerabilities are exploited. Given SAP's widespread adoption in Europe, especially in Germany, France, Italy, Spain, and the UK, the potential impact is significant. The absence of known exploits reduces immediate risk but does not eliminate the threat, especially as attackers may develop exploits once patches are released or if organizations delay remediation.

European organizations should immediately review and tighten access controls around the SAP Fiori 'Manage Service Entry Sheets' app, ensuring that only authorized personnel have access consistent with their roles. Implement detailed logging and monitoring of service entry sheet activities to detect unusual or unauthorized modifications. Employ SAP's recommended security hardening guides and regularly audit user privileges to prevent privilege creep. Since no patch is currently available, consider applying compensating controls such as network segmentation to restrict access to the SAP Fiori app and multi-factor authentication (MFA) for all SAP users to reduce the risk of compromised credentials. Prepare for prompt deployment of SAP security patches once released by maintaining an up-to-date patch management process. Additionally, conduct user training to raise awareness about the risks of privilege escalation and enforce strict change management procedures for critical ERP components.