**Infostealer Logs Pose a Growing Threat to Corporate Security**
A growing number of cybersecurity breaches are being triggered by the discovery of an employee’s password in an infostealer log. What happens when your team’s morning security alert reveals that an employee’s corporate email address has appeared in a newly collected infostealer log? The answer is not as simple as resetting the exposed password, and it’s even more complicated than you might think.
Infostealers like Vidar, RedLine, and Lumma are designed to harvest information stored on infected systems. This can include saved browser passwords, cookies, autofill information, cryptocurrency wallets, system information, VPN configurations, and other authentication artifacts. These stolen credentials are then packaged into infostealer logs, which can contain hundreds or thousands of individual records from a single infection. As these logs make their way through underground forums and marketplaces – increasingly via Telegram channels – defenders face an impossible task: separating a meaningless old password from an identity compromise that could be happening right now.
The problem is further complicated by the fact that many corporate security teams struggle to identify which credentials are truly compromised. According to Flare Research’s Practitioner’s Guide to Monitoring Stealer Logs, approximately 46% of stealer logs containing corporate credentials originate from likely unmanaged or personal devices. This means that defenders may not even be aware of the endpoint that created the exposure in the first place. And if an attacker has already captured an authenticated session cookie, they may have a way into the application without needing the password or another MFA prompt.
As Flare describes it, this isn’t finding a needle in a haystack – it’s finding a specific needle among millions of needles in millions of haystacks. While defenders need to process and validate everything, attackers only need one valid set of credentials to wreak havoc on an organization’s security posture.
In light of these findings, corporate security teams must reassess their approach to monitoring infostealer logs. Rather than simply resetting exposed passwords, they should prioritize monitoring around assets that tell them something about the potential impact – such as corporate domains and subdomains, enterprise identity providers, session cookies, VPN, and RDP endpoints.
The stakes are high: exposure involving credentials and sessions for major productivity SaaS and cloud services is growing approximately 29% annually. Corporate security teams must be prepared to tackle this scale problem head-on, investing in tools and processes that can flag exposed corporate identities and sessions before they turn into account takeover.
In the end, it’s not just about resetting passwords – it’s about understanding the operational challenge posed by infostealer logs and taking proactive steps to mitigate their impact. By doing so, security teams can reduce the risk of identity compromise and protect their organization from the devastating consequences of a successful attack.
Source: Bleeping Computer — 2026-09-03