SAP S/4HANA Rule Processing Flaw Allows Arbitrary ABAP Code Execution
A critical vulnerability in SAP S/4HANA allows authenticated attackers with specific privileges to execute arbitrary ABAP code via crafted input.
Key points
- CVE-2026-89107 carries a CVSS score of 9.9 and is rated Critical.
- The flaw affects SAP S/4HANA Manage Substitution/Validation Rules components.
- Affected versions include S4CORE 105, 106, 107, and 108.
National Vulnerability Database records indicate that SAP S/4HANA contains a critical security flaw identified as CVE-2026-89107. The vulnerability stems from insufficient input validation within the Manage Substitution/Validation Rules functionality, which processes data using a domain-specific scripting language.
At a glance
- CVE
- CVE-2026-89107
- Product
- SAP_SE SAP S/4HANA (Manage Substitution/Validation Rules)
- CVSS
- 9.9 Critical
- Weakness
- code injection
- Exploited
- No known exploitation
An authenticated attacker possessing specific business privileges can exploit this weakness by submitting specially crafted input. This input is incorrectly interpreted as executable ABAP code by the rule processing logic, allowing the attacker to run arbitrary commands within the system.
Technical Context
The Common Vulnerabilities and Exposures database assigns a CVSS score of 9.9 to this issue, classifying its severity as Critical. The weakness is categorized under CWE-94, which relates to improper neutralization of code elements in a script. Successful exploitation results in the execution of arbitrary ABAP code, leading to a full compromise of the affected system.
This compromise impacts confidentiality, integrity, and availability with high severity. The vulnerability exists because the system does not sufficiently validate input processed by the rule definition functionality before interpretation.
Affected Systems
The flaw impacts specific versions of SAP S/4HANA. According to the NVD record, the affected component is the Manage Substitution/Validation Rules module. The vulnerability is present in S4CORE versions 105, 106, 107, and 108.
Organizations running these specific core versions are potentially exposed to this risk. The vulnerability requires the attacker to have an authenticated account with specific business privileges, rather than being accessible to unauthenticated remote users.
What should you do?
Security teams should immediately inventory their SAP S/4HANA environments to identify instances of S4CORE versions 105 through 108. If these versions are in use, monitor for unusual activity related to rule definition and validation processes, as this is the vector for exploitation.
Restrict access to the Manage Substitution/Validation Rules functionality to only those users who strictly require it for business operations. Review existing user privileges to ensure that business roles do not have more access than necessary, reducing the pool of potential attackers.
What to do and how to stay safe: SAP
- Audit your SAP S/4HANA environments to confirm if you are running S4CORE versions 105, 106, 107, or 108.
- Review user access controls to ensure only necessary personnel have privileges to manage substitution and validation rules.
- Monitor system logs for unexpected ABAP code execution or unusual activity within the rule processing logic.
- Contact your SAP vendor representative to inquire about the status of patches for CVE-2026-89107.
Step-by-step guide: Risk Based Vulnerability Management: Prioritize Fixes by Actual Threat
General security guidance from the Threat Times newsroom. It is not confirmed advice from the organisations named in this story.
Frequently asked questions
What is CVE-2026-89107?
It is a critical vulnerability in SAP S/4HANA that allows authenticated attackers to execute arbitrary ABAP code via crafted input in the Manage Substitution/Validation Rules.
Which SAP versions are affected?
The vulnerability affects SAP S/4HANA Manage Substitution/Validation Rules in S4CORE versions 105, 106, 107, and 108.
Is remote code execution possible without authentication?
No, the source material states that an authenticated attacker with specific business privileges is required to exploit this vulnerability.
