As part of Unit 42’s efforts to proactively monitor threats circulating in the wild, I recently came across new Hoaxcalls and Mirai botnet campaigns targeting a post-authentication Remote Code Execution vulnerability in Symantec Secure Web Gateway 22.214.171.124, which is a product that became end-of-life (EOL) in 2015 and end-of-support-life (EOSL) in 2019. There is no evidence to support any other firmware versions are vulnerable at this point in time and these findings have been shared with Symantec. They confirmed the currently exploited vulnerability is no longer present in Symantec Web Gateway 5.2.8. Symantec also wanted to emphasize the point that this vulnerability does not impact Secure Web Gateway solutions, including ProxySG and Web Security Services.
The first instance of this vulnerability being exploited surfaced on April 24th, 2020 as part of an evolution of the Hoaxcalls botnet that was first discovered earlier that same month.
Source: Palo Alto