That's what those hackers do. They no longer change passwords so that the owner of the account won't be alert through their email address that the password has been changed. All they do is log into the compromised account and the post links to malware
If the owner of the account or the mods are not attentive enough, this can appear as though the real own of the account made such a post.
Anyway, good luck to Harizen on recovering his account and perhaps a reminder to use stronger passwords, different passwords for different sites and avoid malicious apps or browser extensions on his device.
I have another assumption that if his computer was hacked. His forum account was open on the browser, and logged in; the hacker could, when he finds the computer idle, control the mouse and keyboard and publish what he wants through the account because he cannot change the password or email if he does not get them through the keylogger or text documents.
@harizen I wish you all the best in returning to your account after the administrators review what you provided and unlock the account. I believe it was locked as a security precaution after the scam ANN topic was published from it.
Now, all that must be done is to find out the real reason that the hacker was able to access your account; you should think and review what you did before this happened. I also advise you to use another device and change the complete account security information if your account has been unlocked until you make sure of this hacker; he cannot reaccess the account again.