Since June, researchers have found and reported several dozen serious flaws in antivirus products from vendors such as Kaspersky Lab, ESET, Avast, AVG Technologies, Intel Security (formerly McAfee) and Malwarebytes. Many of those vulnerabilities would have allowed attackers to remotely execute malicious code on computers, to abuse the functionality of the antivirus products themselves, to gain higher privileges on compromised systems and even to defeat the anti-exploitation defenses of third-party applications.

Exploiting some of those vulnerabilities required no user interaction and could have allowed the creation of computer worms -- self-propagating malware programs. In many cases, attackers would have only needed to send specially crafted email messages to potential victims, to inject malicious code into legitimate websites visited by them, or to plug in USB drives with malformed files into their computers. (...)

https://www.csoonline.com/article/3020459/security/antivirus-software-could-make-your-company-more-vulnerable.html