Yes. Allah compares backbiting to eating the flesh of one's dead brother (49:12). The Prophet ﷺ explained that it is mentioning your brother in a way he dislikes.
Hai orang-orang yang beriman, jauhilah kebanyakan purba-sangka (kecurigaan), karena sebagian dari purba-sangka itu dosa. Dan janganlah mencari-cari keburukan orang dan janganlah menggunjingkan satu sama lain. Adakah seorang diantara kamu yang suka memakan daging saudaranya yang sudah mati? Maka tentulah kamu merasa jijik kepadanya. Dan bertakwalah kepada Allah. Sesungguhnya Allah Maha Penerima Taubat lagi Maha Penyayang.
Hadith
Sahih Muslim 2589
Abu Huraira reported Allah's Messenger (ﷺ) as saying:Do you know what is backbiting? They (the Companions) said: Allah and His Messenger know best. Thereupon he (the Holy Prophet) said: Backbiting implies your talking about your brother in a manner which he does not like. It was said to him: What is your opinion about this that if I actually find (that failing) in my brother which I made a mention of? He said: If (that failing) is actually found (in him) what you assert, you in fact backbited him, and if that is not in him it is a slander
This is general information, not a fatwa. For your own situation, ask a qualified scholar.
Questions about halal and haram
Is backbiting (gheebah) haram?
Yes. Allah compares backbiting to eating the flesh of one's dead brother (49:12). The Prophet ﷺ explained that it is mentioning your brother in a way he dislikes.
