Charlie, my cat, attacking, please help

Hi everyone
haven't been on the forums in a while but severely need your help.

I adopted Charlie when he was 5, he is now 6. He has some matted fur on his skin and his nails could use trimming. I think I am the cause for his vicious behavior. I have a vet appt. In june.

The only time he was semi aggressive was when I first got him. He would hiss and stare me down but he finally adapted.

He was fine with most people. The other day he basically mauled my cousin. Very serious attack. Scratches and bite marks all over her body. Never seen anything so bad and never thought Charlie could do so much harm.
He attacked me the other day and grabbed onto my arm which requires me to go on antibiotics.

I don't have enough money to bring him to the vet till next month in june. I am terrified that he's going to attack again. The BOH called me and told me Charlie is quarantined for ten days and they are going to assess him June 1.

His fur isn't severely matted but he's matted enough.

I'm desperate for help.
Thank you
matt

I think we need a bit more information from you. What was going on with the cat before he attacked you and your cousin?  You keep bringing up his matted fur. Were you trying to brush him or remove the mats? If so, you might have been hurting him unknowingly. Cats don't usually attack for no reason. Please give us more information on the situation surrounding the attacks so we can try to help you.