CVE-2023-25187

An issue was discovered on NOKIA Airscale ASIKA Single RAN devices before 21B. Nokia Single RAN commissioning procedures do not change (factory-time installed) default SSH public/private key values that are specific to a network operator. As a result, the CSP internal BTS network SSH server (disabled by default) continues to apply the default SSH public/private key values. These keys dont give access to BTS, because service user authentication is username/password-based on top of SSH. Nokia factory installed default SSH keys are meant to be changed from operator-specific values during the BTS deployment commissioning phase. However, before the 21B release, BTS commissioning manuals did not provide instructions to change default SSH keys (to BTS operator-specific values). This leads to a possibility for malicious operations staff (inside a CSP network) to attempt MITM exploitation of BTS service user access, during the moments that SSH is enabled for Nokia service personnel to perform troubleshooting activities.

Weakness

The product contains hard-coded credentials, such as a password or cryptographic key.

Affected Software

Extended Description

There are two main variations:

Potential Mitigations

• For outbound authentication: store passwords, keys, and other credentials outside of the code in a strongly-protected, encrypted configuration file or database that is protected from access by all outsiders, including other local users on the same system. Properly protect the key (CWE-320). If you cannot use encryption to protect the file, then make sure that the permissions are as restrictive as possible [REF-7].
• In Windows environments, the Encrypted File System (EFS) may provide some protection.
• For inbound authentication using passwords: apply strong one-way hashes to passwords and store those hashes in a configuration file or database with appropriate access control. That way, theft of the file/database still requires the attacker to try to crack the password. When handling an incoming password during authentication, take the hash of the password and compare it to the saved hash.
• Use randomly assigned salts for each separate hash that is generated. This increases the amount of computation that an attacker needs to conduct a brute-force attack, possibly limiting the effectiveness of the rainbow table method.
• For front-end to back-end connections: Three solutions are possible, although none are complete.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/191.html
• https://cwe.mitre.org/data/definitions/70.html

References

• http://packetstormsecurity.com/files/173055/Nokia-ASIKA-7.13.52-Private-Key-Disclosure.html
• https://Nokia.com
• https://www.nokia.com/about-us/security-and-privacy/product-security-advisory/cve-2023-25187/
• http://packetstormsecurity.com/files/173055/Nokia-ASIKA-7.13.52-Private-Key-Disclosure.html
• https://Nokia.com
• https://www.nokia.com/about-us/security-and-privacy/product-security-advisory/cve-2023-25187/