Hard-coded Key for PIN Encryption in dormakaba Kaba exos 9300

Vulnerability Description

The program libraries (DLL) and binaries used by exos 9300 contain multiple hard-coded secrets. One notable example is the function "EncryptAndDecrypt" in the library Kaba.EXOS.common.dll. This algorithm uses a simple XOR encryption technique combined with a cryptographic key (cryptoKey) to transform each character of the input string. However, it's important to note that this implementation does not provide strong encryption and should not be considered secure for sensitive data. It's more of a custom encryption approach rather than a common algorithm used in cryptographic applications. The key itself is static and based on the founder's name of the company. The functionality is for example used to encrypt the user PINs before storing them in the MSSQL database.

References

• https://r.sec-consult.com/dormakaba
• https://r.sec-consult.com/dkexos
• https://www.dormakabagroup.com/en/security-advisories