

Telegram sends a one-time password to verify a new login, but this does not make an account completely safe. Hackers, scammers, and even someone with brief access to your phone can still get into your Telegram account without ever asking for that OTP.
This risk applies to anyone who uses the app, from casual users to people running business or community channels. The methods mostly rely on stolen sessions, malware, or old login sessions that were never closed, rather than breaking Telegram's own systems.
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Telegram allows a single account to stay logged in on several devices at once, and each of those sessions works without asking for the OTP again. If a hacker manages to steal an active session through malware on the phone or a fake app that copies login data, they can access the account instantly.
Security researchers note that malicious files, often disguised as APKs on Android, can silently steal session information stored on the device. Once that data reaches an attacker's system, they can open Telegram as if they were the real user, without a password or code.
Public Wi-Fi networks add another layer of risk. Experts point out that unsecured networks make it easier for someone to intercept data flowing between a phone and Telegram's servers, especially when using Telegram Web on a shared or public computer.
Phishing remains common on Telegram too. A fake login page that looks identical to Telegram's real site can trick users into entering their credentials directly, handing over access without any OTP involved.
A few habits go a long way in preventing this kind of hack:
Turn on Two-Step Verification in Telegram's settings for an extra password layer.
Add a passcode lock inside the app so it cannot be opened even with an unlocked phone.
Check the Devices section regularly and log out of sessions you do not recognise.
Avoid downloading APK files or clicking links from unknown senders.
Keep the app updated, since Telegram regularly patches security flaws.
These steps together make it much harder for anyone to slip into an account unnoticed.