CVE-2026-27689
📋 TL;DR
This CVE describes a denial-of-service vulnerability in SAP systems where authenticated users can trigger excessive resource consumption by calling a remote function module with large loop parameters. This affects SAP systems with vulnerable function modules exposed to authenticated users. The vulnerability allows attackers to render systems unavailable by exhausting system resources.
💻 Affected Systems
- SAP NetWeaver Application Server ABAP
- SAP ABAP Platform
⚠️ Manual Verification Required
This CVE does not have specific version information in our database, so automatic vulnerability detection cannot determine if your system is affected.
Why? The CVE database entry doesn't specify which versions are vulnerable (no version ranges provided by the vendor/NVD).
🔒 Custom verification scripts are available for registered users. Sign up free to download automated test scripts.
- Review the CVE details at NVD
- Check vendor security advisories for your specific version
- Test if the vulnerability is exploitable in your environment
- Consider updating to the latest version as a precaution
⚠️ Risk & Real-World Impact
Worst Case
Complete system unavailability affecting all users and services, requiring system restart and potential data loss from interrupted transactions.
Likely Case
Performance degradation or temporary service interruption for affected application components, impacting business operations.
If Mitigated
Minimal impact with proper access controls, monitoring, and resource limits in place.
🎯 Exploit Status
Exploitation requires authenticated access but is technically simple once access is obtained.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: As specified in SAP Note 3719502
Vendor Advisory: https://me.sap.com/notes/3719502
Restart Required: Yes
Instructions:
1. Review SAP Note 3719502 for specific patch details. 2. Apply relevant SAP security patches. 3. Restart affected systems. 4. Verify patch application through transaction SPAM/SAINT.
🔧 Temporary Workarounds
Restrict Function Module Access
allLimit access to vulnerable remote-enabled function modules using authorization objects S_RFC and S_ADMI_FCD.
Use transaction SE93 or SU24 to adjust authorizations
Implement Resource Limits
allConfigure system parameters to limit resource consumption for RFC calls.
Adjust rdisp/rfc_max_own_login, rdisp/rfc_max_login, and related parameters in instance profile
🧯 If You Can't Patch
- Implement strict access controls to limit which users can execute remote function modules
- Deploy monitoring and alerting for abnormal resource consumption patterns
🔍 How to Verify
Check if Vulnerable:
Check if your system version matches affected versions in SAP Note 3719502 and verify if vulnerable function modules are exposed.Check Version:
Execute transaction SM51 or run report RSVERSION to check SAP kernel and system version.Verify Fix Applied:
Verify patch application through transaction SPAM/SAINT and test that the vulnerability is no longer exploitable.📡 Detection & Monitoring
Log Indicators:
- Excessive RFC call durations in STAD logs
- High CPU/memory consumption in system logs
- Multiple failed RFC connection attempts
Network Indicators:
- Unusual volume of RFC traffic to specific function modules
- Sustained high network activity from single sources
SIEM Query:
source="sap_logs" AND (message="*RFC*" OR message="*function module*") AND duration>threshold