A vulnerability has been found in Bitdefender Antivirus Free 2020 that could allow an attacker to load unsigned code that could lead to privilege escalation.
Safebreach reported the main issue with the product is the code integrity guard mechanism is not enforced allowing an attacker to load unsigned code. The danger here is particularly high because the software runs as a NT AUTHORITY\SYSTEM, the most privileged user account making such access highly valuable to an unauthorized person.
“The vulnerability gives attackers the ability to load and execute malicious payloads using a signed service. This ability might be abused by an attacker, for example to achieve Application Whitelisting Bypass for purposes such as execution and evasion,” Safebreach wrote.
The root causes behind the vulnerability are the lack of safe DLL loading due to having an uncontrolled search path and that no digital certificate validation is made against the binary.
Safebreach reported the issue to Bitdefender on July 17. That company immediately responded and was able to confirm the issue by August 14. Five days later BitDefender published an advisory and issued CVE-2019-15295.
Bitdefender told SC Media that the issue was submitted by Safebreach through the security firm’s bug bounty program
“We have coordinated this announcement with the original reporters and published our own advisory on our website. The issue has been fixed and we have automatically updated our customer base before the releases went public. We launched our bug bounty program two years ago to increase the security and reliability of our code base and provide best-in class security that our customers expect of us.,” Bogdan “Bob” Botezatu, director of threat research and reporting at Bitdefender.