CVE-2025-42939 is an authorization vulnerability classified under CWE-863 affecting SAP SE's SAP S/4HANA product, specifically the Manage Processing Rules functionality for Bank Statements. The vulnerability arises because the application fails to properly verify whether an authenticated user has the necessary permissions before allowing deletion of conditions from shared processing rules. An attacker with basic authenticated privileges can manipulate request parameters to delete conditions from any shared rule belonging to any user. This unauthorized deletion compromises the integrity of the processing rules, potentially leading to incorrect financial processing or rule enforcement. The vulnerability does not affect confidentiality or availability, as it does not expose sensitive data or cause service disruption. The CVSS v3.1 score is 4.3 (medium severity), reflecting low attack complexity, network attack vector, and the need for low privileges but no user interaction. Affected SAP S/4HANA versions include S4CORE 104 through 109. No patches were linked at the time of reporting, and no exploits are known in the wild. The flaw highlights a critical gap in authorization checks within a core financial processing module, which could be leveraged by insiders or compromised accounts to alter financial rules undetected.

For European organizations, particularly those in banking, finance, and enterprises relying heavily on SAP S/4HANA for financial operations, this vulnerability poses a risk to the integrity of financial processing rules. Unauthorized deletion of shared rule conditions could lead to incorrect processing of bank statements, potentially causing financial discrepancies, compliance issues, or erroneous transaction handling. While confidentiality and availability remain unaffected, the integrity compromise could undermine trust in financial data and processes, leading to audit failures or regulatory scrutiny. Organizations with complex shared rule configurations are at higher risk, as attackers could selectively delete critical conditions. The impact is heightened in environments where multiple users share processing rules, increasing the attack surface. Given the widespread use of SAP S/4HANA in Europe, the vulnerability could affect a significant number of enterprises, especially those with less stringent internal access controls or monitoring.

1. Apply SAP vendor patches immediately once released for the affected S/4HANA versions (104 to 109). 2. Implement strict role-based access controls (RBAC) to limit who can access and modify processing rules, ensuring only authorized personnel have such privileges. 3. Enable detailed logging and monitoring of changes to processing rules, with alerts for deletions or modifications to shared rules. 4. Conduct regular audits of processing rules to detect unauthorized changes promptly. 5. Use SAP’s security configuration guides to harden the Manage Processing Rules module and restrict API or interface access. 6. Educate users about the risks of credential compromise and enforce strong authentication mechanisms to reduce the chance of attacker access. 7. Consider implementing additional application-layer authorization checks or compensating controls if patching is delayed. 8. Review and segregate duties to minimize the risk of insider threats exploiting this vulnerability.