CVE-2021-47813 affects Backup Key Recovery version 2.2.7, containing a denial of service vulnerability in the registration code input field. Attackers can exploit this by pasting a large buffer of 256 repeated characters into the registration key field, causing the application to become unstable and potentially crash. This is a buffer overflow vulnerability that leads to application denial of service. The vulnerability has been documented with proof-of-concept exploits available on Exploit-DB. Multiple security advisories and references are available for this CVE.