Avoid playing without a firewall rule or playing at all!
A glance at RockstarsSupport siteshows that players are following through with that call.
The exploit is partial remote code execution, Tez2 claimed in anothertweet.

Paid mod menus are racing as speak to abuse this to the further extent.
This could transform into something much worse to extend beyond a game and affect your PC.
Yet Speyedr has taken Guardian down temporarily in the hope that Rockstar can correct the issue.

Download link is removed until the RCE exploit is fixed, Speyedr said on the Guardiangitlabpage.
I don’t want beginners using Guardian incorrectly when there’s such a huge risk.
Mod menus will exploit the hell out of this.
like just take a break.
Just be careful if youre heading out onto the streets of Los Santos anytime soon.