One of the reasons why virus protection may not recognize KeenVal J is because it uses code obfuscation techniques to evade detection. This means that the malware code is written in a way that makes it difficult for antivirus scanners to identify it as malicious. Additionally, KeenVal J may use rootkit techniques to hide its presence and prevent antivirus software from accessing or removing its files.
To protect against Trojan horse downloaders like KeenVal J, it is important to keep antivirus software up to date and practice caution when opening emails or downloading files from untrusted sources. Additionally, using strong security measures such as two-factor authentication and a firewall can help to further reduce the risk of infection.