Credential stuffing is one of the most common ways attackers get into online accounts because it exploits a familiar human habit: password reuse. Recent reporting on 2025 attack trends shows that stolen credentials remained a major entry point, with compromised credentials accounting for 22% of confirmed breaches.
This article explains the main tools criminals use to steal passwords, how those tools work, why residential proxies help attackers evade detection. And why anti-malware products like Panda Dome matter before the attack chain even reaches the login page.
Key takeaways
- Infostealer malware captures saved passwords, cookies, and browser data from infected devices.
- Attackers package stolen logins into combolists, then replay them at scale using automated credential-stuffing frameworks such as OpenBullet and SilverBullet.
- Residential proxies make attack traffic look like it comes from ordinary home internet users. This helps criminals bypass rate limits and IP blocking.
- Anti-malware tools help stop the infection stage. This is critical because compromised PCs can become part of the broader botnet. And credential theft pipeline.
How password theft starts
The first step in many credential stuffing campaigns is not a guessed password – it is malware. Infostealers such as Lumma, RedLine, StealC, and Acreed are designed to quietly harvest passwords stored in browsers, session cookies, autofill data, and tokens from an infected computer. They act like a digital thief that raids the browser’s memory and clipboard rather than breaking into an account one guess at a time.
Once stolen, those credentials are cleaned up and organized into combolists –files of username-password pairs ready for reuse. Criminals trade them across forums, Telegram channels, and private markets, because fresh logs from recent infections are more likely to still work. This is important because users often reuse passwords across services, making one stolen login potentially useful on many websites.
The tools attackers use
Attackers rely on a small set of widely available tools that automate the entire process. OpenBullet and SilverBullet are commonly used credential-stuffing frameworks. They can load combolists, send login attempts to a target website, and record which accounts work. To a non-technical user, these tools are basically automated checkout lines for criminals. They keep trying stolen usernames and passwords until they find valid matches that allow them to break in.
These tools are powerful because they can mimic normal browser behavior, vary request timing, and test huge numbers of accounts without human effort. They also use “configs,” which are prebuilt instructions for specific websites, so attackers do not need to understand the target service in detail. That industrializes account takeover by turning theft into a repeatable workflow rather than a one-off attack.
Why residential proxies matter
Residential proxies are one of the biggest reasons credential stuffing remains effective. Attackers avoid data center IPs that security systems can easily flag and block. Instead, they route traffic through devices that look like ordinary home internet connections. From the website’s perspective, the traffic looks much more like a real person in a normal household than a bot in a server farm.
This helps criminals bypass rate limiting, IP reputation checks, and other controls that look for large numbers of failed logins from the same source. By spreading attempts across many residential addresses, attackers keep each IP below alert thresholds. And make the campaign harder to distinguish from legitimate user activity. Some botnets are even used to supply these proxy networks, which means infected consumer devices can be turned into part of the attack infrastructure itself.
Why anti-malware comes first
Anti-malware tools help stop credential stuffing at the most important point in the chain – the infected device. If the malware never gets onto the computer, it cannot steal saved passwords, browser cookies, or session tokens in the first place. Panda Dome Premium includes antivirus, anti-malware, anti-phishing, firewall, and dark web monitoring features, which supports that first-line defense approach.
Anti-malware lessens chances of your computer becoming both a source of stolen credentials and a relay point for someone else’s attack.
A better defense stack
Anti-malware is the start, not the end, of good protection. Users should also use unique passwords, turn on MFA wherever possible, and avoid saving credentials in places that malware can easily reach. For organizations, the most effective approach combines phishing-resistant MFA, rate limiting, device intelligence, and bot detection with endpoint protection on every managed device.
The larger lesson is that credential stuffing is not just a login problem. It is algo an endpoint problem, a password hygiene problem, and a botnet problem at the same time. If a device is compromised, the attacker can steal credentials, join the machine to a larger proxy network. And reuse the data elsewhere.
That is why anti-malware products like Panda Dome are essential. They help break the chain before stolen data ever reaches the market.
Conclusion
Credential stuffing works because attackers combine stolen credentials, malware, and proxy networks into a highly scalable system. The best way to weaken that system is to stop the malware on the device first. Then layer in stronger authentication and account protections.
Panda Dome fits into that strategy as the first line of defense against the infections that make password theft and botnet abuse possible.