An issue was discovered in Open Source Social Network (OSSN) through 5.3. A user-controlled file path with a weak cryptographic rand() can be used to read any file with the permissions of the webserver. This can lead to further compromise. The attacker must conduct a brute-force attack against the SiteKey to insert into a crafted URL for components/OssnComments/ossn_com.php and/or libraries/ossn.lib.upgrade.php.
The product uses a Pseudo-Random Number Generator (PRNG) in a security context, but the PRNG’s algorithm is not cryptographically strong.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Open_source_social_network | Opensource-socialnetwork | * | 5.3 (including) |
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.