The use of a cryptographically weak pseudo-random number generator in the password reset feature of FortiPortal before 6.0.6 may allow a remote unauthenticated attacker to predict parts of or the whole newly generated password within a given time frame.
Weakness
The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG’s algorithm is not cryptographically strong.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Fortiportal | Fortinet | * | 4.0.4 (including) |
| Fortiportal | Fortinet | 4.1.0 (including) | 4.1.2 (including) |
| Fortiportal | Fortinet | 4.2.0 (including) | 4.2.4 (including) |
| Fortiportal | Fortinet | 5.0.0 (including) | 5.0.3 (including) |
| Fortiportal | Fortinet | 5.1.0 (including) | 5.1.2 (including) |
| Fortiportal | Fortinet | 5.2.0 (including) | 5.2.7 (excluding) |
| Fortiportal | Fortinet | 5.3.0 (including) | 5.3.7 (excluding) |
| Fortiportal | Fortinet | 6.0.0 (including) | 6.0.6 (excluding) |
Extended Description
When a non-cryptographic PRNG is used in a cryptographic context, it can expose the cryptography to certain types of attacks. Often a pseudo-random number generator (PRNG) is not designed for cryptography. Sometimes a mediocre source of randomness is sufficient or preferable for algorithms that use random numbers. Weak generators generally take less processing power and/or do not use the precious, finite, entropy sources on a system. While such PRNGs might have very useful features, these same features could be used to break the cryptography.