Zero-Day Advisory

Fortinet Discovers Avast Security Product Security Bypass Vulnerability


Fortinet's FortiGuard Labs has discovered Security Bypass vulnerability in Avast.

It has been discovered that Avast self-defense driver can be bypassed by user-mode program. It would allow adversary to disable critical product functionalities. The flaw resides in Avast's self-defense driver aswSp.sys which allows adversary to modify Avast protected registry key. By exploiting the vulnerability, attackers could have the product become completely nonfunctional or partially malfunction by disabling the product update.


Users should apply the solution provided by Avast.

Additional Information

Following products and versions are affected.

  AVAST Free Antivirus 12.2.2276  and below


This vulnerability was discovered by Wayne Low of Fortinet's FortiGuard Labs.

IPS Subscription

Fortinet customers who subscribe to Fortinet's intrusion prevention (IPS) service should be protected against this vulnerability with the appropriate configuration parameters in place. Fortinet's IPS service is one component of FortiGuard Subscription Services, which also offer comprehensive solutions such as antivirus, Web content filtering and antispam capabilities. These services enable protection against threats on both application and network layers. FortiGuard Services are continuously updated by FortiGuard Labs, which enables Fortinet to deliver a combination of multi-layered security intelligence and true zero-day protection from new and emerging threats. These updates are delivered to all FortiGate, FortiMail and FortiClient products. Fortinet strictly follows responsible disclosure guidelines to ensure optimum protection during a threat's lifecycle.