Known v1.3.1+2020120201 was discovered to allow attackers to perform an account takeover via a host header injection attack.
blog.jitendrapatro.me/multiple-vulnerabilities-in-idno-known-php-cms-software/
github.com/idno/known
github.com/swisskyrepo/PayloadsAllTheThings/tree/master/Account%20Takeover#account-takeover-through-password-reset-poisoning
www.pethuraj.com/blog/how-i-earned-800-for-host-header-injection-vulnerability/