Legacy versions are vulnerable to memory leaks and CPU exhaustion. For example, a memory leak can occur if the deny_file option is enabled, allowing an attacker to exhaust system memory. Additionally, crafted "glob" expressions in STAT commands can trigger high CPU consumption.
Versions before 3.0.2 often have flaws in how they parse deny_file patterns, potentially allowing users to access restricted files. How to Fix and Secure vsftpd vsftpd 208 exploit github fix
The vsftpd 2.0.8 version is frequently cited in security walkthroughs, often appearing on vulnerable lab machines like those found on VulnHub . While version 2.0.8 itself does not contain the infamous "backdoor" exploit (which actually targeted version 2.3.4), it is considered a legacy version with several known vulnerabilities that require patching or upgrading to modern releases like vsftpd 3.0+. Understanding the Vulnerability Landscape Legacy versions are vulnerable to memory leaks and