Phishing
Fake Telegram download sites can carry malware
Security researchers have documented cloned Telegram websites, reached through search ads, that offer a “Telegram for Windows” installer which actually delivers information-stealing malware.
The official downloads are on telegram.org and desktop.telegram.org, or in your phone’s official app store. Do not install Telegram from a link in a chat, an ad, or a file someone sent you.
Read the web address letter by letter before you download. If you are unsure, type the address yourself.