CVE-2023-46740

CubeFS is an open-source cloud-native file storage system. Prior to version 3.3.1, CubeFS used an insecure random string generator to generate user-specific, sensitive keys used to authenticate users in a CubeFS deployment. This could allow an attacker to predict and/or guess the generated string and impersonate a user thereby obtaining higher privileges. When CubeFS creates new users, it creates a piece of sensitive information for the user called the “accessKey”. To create the accesKey, CubeFS uses an insecure string generator which makes it easy to guess and thereby impersonate the created user. An attacker could leverage the predictable random string generator and guess a users access key and impersonate the user to obtain higher privileges. The issue has been fixed in v3.3.1. There is no other mitigation than to upgrade.

Weakness

The product uses insufficiently random numbers or values in a security context that depends on unpredictable numbers.

Affected Software

Potential Mitigations

• Use a well-vetted algorithm that is currently considered to be strong by experts in the field, and select well-tested implementations with adequate length seeds.
• In general, if a pseudo-random number generator is not advertised as being cryptographically secure, then it is probably a statistical PRNG and should not be used in security-sensitive contexts.
• Pseudo-random number generators can produce predictable numbers if the generator is known and the seed can be guessed. A 256-bit seed is a good starting point for producing a “random enough” number.

Related Attack Patterns

• https://cwe.mitre.org/data/definitions/112.html
• https://cwe.mitre.org/data/definitions/485.html
• https://cwe.mitre.org/data/definitions/59.html

References

• https://github.com/cubefs/cubefs/commit/8555c6402794cabdf2cc025c8bea1576122c07ba
• https://github.com/cubefs/cubefs/security/advisories/GHSA-4248-p65p-hcrm