CVE-2023-32251

A vulnerability has been identified in the Linux kernels ksmbd component (kernel SMB/CIFS server). A security control designed to prevent dictionary attacks, which introduces a 5-second delay during session setup, can be bypassed through the use of asynchronous requests. This bypass negates the intended anti-brute-force protection, potentially allowing attackers to conduct dictionary attacks more efficiently against user credentials or other authentication mechanisms.

Weakness

The product does not implement sufficient measures to prevent multiple failed authentication attempts within a short time frame, making it more susceptible to brute force attacks.

Affected Software

Potential Mitigations

• Common protection mechanisms include:

• Use a vetted library or framework that does not allow this weakness to occur or provides constructs that make this weakness easier to avoid.

• Consider using libraries with authentication capabilities such as OpenSSL or the ESAPI Authenticator. [REF-45]

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/16.html
• https://cwe.mitre.org/data/definitions/49.html
• https://cwe.mitre.org/data/definitions/560.html
• https://cwe.mitre.org/data/definitions/565.html
• https://cwe.mitre.org/data/definitions/600.html
• https://cwe.mitre.org/data/definitions/652.html
• https://cwe.mitre.org/data/definitions/653.html

References

• https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=b096d97f47326b1e2dbdef1c91fab69ffda54d17
• https://www.zerodayinitiative.com/advisories/ZDI-23-699/