Inside Nifty.com Stealer Logs: 1,547 Passwords Harvested

HEROIC security researchers identified a stealer log targeting Nifty.com users that was posted to a Telegram channel on July 12, 2026. The log file contains 1,547 individual records, each pairing an email address with a plaintext password and the URL where the credentials were captured. Nifty.com is a prominent Japanese internet service and web portal operated by Nifty Corporation, serving millions of users across email, web hosting, and online services.

The technical structure of this stealer log reveals credentials harvested directly from infected endpoints. Unlike server-side breaches where attackers exfiltrate a database, these records were pulled from individual devices by malware that intercepted browser-stored passwords and active login sessions. This origin makes the credentials highly accurate and current.

Why Plaintext Storage Makes These Credentials Weaponized on Arrival

The 1,547 passwords in this log require no post-processing to exploit. They are stored in plaintext — the exact characters each victim used to authenticate. In the threat landscape, this is the difference between raw material and a finished weapon: hashed passwords need time and resources to crack, but plaintext credentials are operational from the moment of exfiltration.

For the individuals in this dataset, the implication is stark. Any threat actor who downloads this file from Telegram can begin account takeover attempts immediately. The combination of a working email address, a known password, and the URL of the target service creates a complete attack vector that requires no additional intelligence gathering.

What Was Exposed in the Nifty.com Dump

• Email Addresses — Nifty.com email addresses used as account identifiers across the Nifty ecosystem and potentially as recovery addresses for external services including banking, e-commerce, and social platforms.
• Plaintext Passwords — Cleartext passwords captured by the infostealer at the point of use or extracted from browser credential stores, providing attackers with verified, working authentication strings.
• URLs — Target URLs recorded alongside each credential pair, documenting the exact login endpoints where victims authenticated and giving attackers a precise map of exploitable accounts.

Why 1,547 Credential Pairs Fuel Large-Scale Account Takeovers

Each record in this stealer log is a self-contained attack package: an identity, a password, and a target. When multiplied across 1,547 victims, the potential for damage grows exponentially. Attackers do not manually test these credentials one by one — they load them into automated credential stuffing frameworks that cycle through login portals at machine speed.

The risk escalates dramatically for victims who reuse passwords. A single Nifty.com password that also protects an online banking account, a corporate VPN, or a cloud storage service turns one compromised credential into a chain of breached accounts. Security industry data suggests that password reuse rates remain above 60%, making this a near-certainty for a significant portion of the 1,547 affected users.

How Stealer Logs Extract Credentials at the Endpoint Level

Infostealer malware operates at the device level, bypassing server-side security measures entirely. Common infection vectors include trojanized applications, malicious browser extensions, phishing payloads, and exploit kits served through compromised advertisements. Once active on a device, the malware targets browser SQLite databases where credentials are stored, intercepts form submissions in real time, and siphons session cookies that can bypass even two-factor authentication.

The extracted data is structured into log files organized by domain or service, then transmitted to the operator's infrastructure. These logs frequently surface on Telegram within days of collection, reaching a broad audience of buyers and opportunistic attackers. The Nifty.com dataset represents one such log — a technically organized collection of stolen credentials now available for exploitation by anyone who finds the channel.

Check If Your Credentials Were Exposed in This Leak

If you have a Nifty.com account or use Nifty.com email for any online services, verify your exposure now. HEROIC provides a free breach scanning tool that checks your email address against a database containing over 400 billion compromised records, including stealer log datasets like this Nifty.com file.

Enter your email to search for matches. If your credentials appear, take immediate action: change your Nifty.com password, update any other account where you used the same password, enable multi-factor authentication on all supported services, and run endpoint security software to detect and remove any infostealer malware that may still be active on your devices.