Not very surprising you got ransomware'd when your server was last updated nearly 10 years ago:
NAYANAβs website runs on Linux kernel 2.6.24.2, which was compiled back in 2008. [...] Additionally, NAYANAβs website uses Apache version 1.3.36 and PHP version 5.1.4, both of which were released back in 2006. Apache vulnerabilities and PHP exploits are well-known;[...]. The version of Apache NAYANA used is run as a user of nobody(uid=99), which indicates that a local exploit may have also been used in the attack.