The Poczta.onet.pl Leak: 10,970 Passwords Exposed. Yours Might Be One.

In June 2026, HEROIC analysts identified a combolist uploaded to a Telegram channel by an individual user, tied to the poczta.onet.pl webmail service. The file contained 10,970 records pairing email addresses with plaintext passwords and the URLs where those credentials were originally used. Why is this dangerous? Because the passwords in this file are stored in plaintext, anyone who downloads it can log into an account immediately with no cracking or guesswork required. If the exposed poczta.onet.pl login is reused anywhere else, an attacker can try that same email and password combination on banking sites, social media, and shopping accounts within minutes. Here is what was exposed in the poczta.onet.pl leak: email addresses, plaintext passwords, and associated URLs. Why this matters: Combolists like this one are traded and re-traded across Telegram and dark web forums long after they first appear, which means the exposure window for these 10,970 accounts does not close when the original post disappears. Stolen credentials like these rarely stay in one place. Attackers feed lists like this into automated tools that test each email and password pair against banking sites, email providers, and online retailers, a technique known as credential stuffing. When a password is reused, one exposed account can lead directly to account takeover, identity theft, or financial fraud on completely unrelated services. How This Combolist Ended Up on Telegram: A combolist is simply a compiled list of email or username and password pairs, often stitched together from older breaches, phishing kits, or malware logs and repackaged for resale or free distribution. Unlike a single hacked database, a combolist can mix data from several unrelated sources, so the poczta.onet.pl entries here may have been pulled together from more than one prior incident and repackaged as one file. Check If Your poczta.onet.pl Account Was Exposed: You do not have to wait to find out if your information is part of a leak like this one. HEROIC's free breach scanner checks your email address against a database of more than 400 billion exposed records, including combolists and stealer logs like this one, and tells you immediately if your credentials have shown up in a known breach. If you find a match, change that password right away, and avoid reusing it anywhere else.