Flaws in the Oracle Thin Client Framework API used in the General Ledger and Work in Progress modules of Oracle EBS leave thousands of firms vulnerable to financial fraud.

Specialist Oracle security firm Onapsis has released a summary of exploits based on these vulnerabilities which they name Payday.

One proof of concept demonstration shows how an approved supplier payment can be changed, this happens after it has already gone through the EBS approval workflow and been signed-off by authorised employees.  In the demonstration the destination bank account details were amended before the instructions were transmitted to the bank and a trigger was created in the Oracle database to then revert the changes in the database (and remove any trace in the audit logs) once the payment instructions had been transmitted.  The net result is, the payment instructions that went to the bank were different from the transactions recorded in the Oracle EBS database and there is no evidence left of the changes – except for the bank payment file itself.

Another proof of concept showed cheques being printed and then all trace of the cheques being removed from the system.

The two relevant CVE ( CVE-2019-2638 and CVE-2019-2633) were patched in the April 2019 release from Oracle, yet Onapsis estimate up to half of all ERP systems remain unpatched.

The underlying  improper access control vulnerabilities have a CVSS score of 9.9 out of 10 meaning they are easy to exploit and have a significant impact on the integrity and security of the affected systems.

ERP systems, especially if they have been customised, can be challenging to patch due to the significant operational impact if they are not available during business hours.  However, as these vulnerabilities demonstrate, the business is at significant risk if unpatched financial systems allow transactions to be modified to divert funds.