CVE-2021-30047 Scanner

vsftpd, short for Very Secure FTP Daemon, is a widely used FTP server for Unix systems. It is favored due to its security, speed, and shielding against common FTP vulnerabilities. System administrators utilize vsftpd for secure file transfers over networks. Organizations rely on it for handling extensive FTP transactions efficiently. Its deployment includes environments requiring stable and secure FTP services. Given its extensive application, vulnerabilities in vsftpd can significantly impact numerous systems globally.

The Denial of Service (DoS) vulnerability in vsftpd allows remote attackers to render the service unavailable. This exploit involves sending crafted FTP commands to the server. Failure to handle these malformed inputs results in service disruption. Attackers can capitalize on this to exhaust server resources. Successfully exploiting this flaw leads to the degradation of service availability. System administrators must monitor for such activities and apply patches promptly.

Technically, the vulnerability surfaces in vsftpd versions prior to 3.0.3. Attackers exploit this by sending malformed FTP commands. The server's inability to process these malformed commands correctly triggers a DoS condition. This involves targeting specific FTP communications that the server mishandles. The vulnerable parameter is within the FTP command structure. Ensuring the server can withstand such crafted communications is imperative for security.

When exploited, a DoS attack can cause significant disruption. It exhausts system resources, leading to service outages. User transactions are halted, affecting business continuity. Organizations may face reputational damage as users experience service unavailability. Additionally, recovering from such attacks can demand substantial efforts and resources. It underscores the necessity for timely updates and patches.

REFERENCES

• https://github.com/kuppamjohari/vsftpd-3.0.3-DoS