Error Page Content Spoofing or Text Injection

How it was found

Description: hello sir, i found that one you once you write any thing after / in www.cfptime.org/ is reflected in the error page example go to www.cfptime.org/texthere you will see test here in the 404 error page

Steps To Reproduce:

1.go https://www.cfptime.org/!!!ATENTION!%20This%20server%20is%20on%20Maintenance%20please%20go%20to%20WWW.EVIL.COM%20since%20it%20was

2.see that The requested URL /!!!ATENTION! This server is on Maintenance please go to WWW.EVIL.COM since it was not found on this server. is found in the page i added attached picture as poc

Supporting Material/References:

i attached picture as poc

Impact

attacker could use this as phishing process to attack users