5 Signs Your Business Has Already Been Compromised

Most businesses imagine a cyberattack as a dramatic event — screens going dark, ransom notes flashing, data wiped in an instant. But the reality is far more insidious. The average data breach takes over 200 days to detect, according to IBM's annual Cost of a Data Breach report. That means attackers could be lurking inside your network right now, quietly exfiltrating data, escalating privileges, and laying the groundwork for a devastating strike — all without you knowing.

Knowing the warning signs of a compromise is the first step toward limiting damage and restoring control. Here are five red flags every organization should watch for.

1. Unusual Network Traffic Patterns

One of the earliest and most telling indicators of a breach is anomalous network traffic. This could manifest as sudden spikes in bandwidth usage during off-hours, unexpected data transfers to unfamiliar external IP addresses, or protocols being used in ways they shouldn't be. For example, DNS tunneling — where attackers encode stolen data inside DNS queries — can slip past traditional firewalls unnoticed.

If your monitoring tools show traffic flowing to geographic regions where you have no customers, partners, or infrastructure, that is a major red flag. Attackers often route exfiltrated data through servers in jurisdictions that are less cooperative with international law enforcement, making detection and recovery more difficult.

2. Unexplained Account Lockouts and Credential Issues

When employees start reporting repeated account lockouts, password resets they never requested, or multi-factor authentication prompts they didn't trigger, you may be dealing with an active credential-stuffing or brute-force campaign. Attackers frequently use stolen credential databases from previous breaches to attempt logins across multiple services — a technique known as credential stuffing.

Even more alarming is the creation of new administrator accounts that no one in your IT team authorized. This is a hallmark of privilege escalation — an attacker who has already breached a low-level account and is now working to gain full control of your environment. Review your Active Directory or identity provider logs regularly for any accounts or permission changes you cannot explain.

3. Slow Systems and Strange Processes

A noticeable degradation in system performance — sluggish applications, servers running at high CPU utilization without clear cause, or endpoints rebooting spontaneously — can point to malicious activity. Cryptominers, backdoor implants, and command-and-control (C2) beacons all consume resources and leave traces in process lists and task managers.

Pay close attention to processes running under system-level privileges that have generic or slightly misspelled names — for instance, "svch0st.exe" instead of the legitimate "svchost.exe." Attackers rely on these subtle disguises to blend in. If your security team cannot account for every running process on a critical server, treat it as a potential compromise until proven otherwise.

4. Missing or Modified Files

If critical configuration files, database records, or log entries have been altered, deleted, or encrypted without authorization, your environment has almost certainly been tampered with. Ransomware is the most obvious culprit — it encrypts files and demands payment — but subtler attacks may simply modify log files to erase evidence of intrusion or alter financial records for fraud.

Implement file integrity monitoring (FIM) on your most sensitive systems. FIM solutions create cryptographic hashes of critical files and alert you the moment anything changes. Without this capability, an attacker could be modifying your systems for weeks before anyone notices.

5. Unusual Outbound Connections

Compromised machines often establish persistent outbound connections to command-and-control servers. These beacons allow attackers to issue commands remotely, download additional payloads, and exfiltrate data in small, hard-to-detect increments. The connections may use encrypted channels over standard ports like 443 (HTTPS) to avoid detection by basic firewall rules.

Watch for endpoints that regularly reach out to newly registered domains, dynamic DNS services, or IP addresses with no associated legitimate business purpose. Threat intelligence feeds can help you cross-reference suspicious destinations against known malicious infrastructure, but sophisticated attackers rotate their infrastructure frequently, which is why behavioral analysis is essential.

What to Do If You Spot These Signs

If any of these indicators resonate with what you are seeing in your environment, speed is critical. First, isolate affected systems from the network to prevent lateral movement. Second, preserve all logs and forensic evidence — never wipe a machine before capturing a disk image. Third, engage your incident response team or a trusted external partner to conduct a thorough investigation. Finally, notify relevant stakeholders and, if required by regulation, report the breach to the appropriate authorities.

Most importantly, resist the temptation to simply "patch and move on." Without understanding the attacker's full scope of access — every backdoor planted, every credential stolen — you risk leaving the door open for a return visit.

How Prootego XDR Detects Compromises Early

Traditional security tools often work in silos — your firewall sees network traffic, your antivirus scans files, and your SIEM collects logs, but none of them share context in real time. Prootego XDR breaks down these silos by correlating signals from endpoints, networks, cloud workloads, and identity systems into a single, unified detection engine.

With AI-driven behavioral analytics, Prootego XDR establishes a baseline of normal activity for every user, device, and application in your environment. When something deviates — a user accessing files they have never touched, a server opening connections to a foreign IP at 3 AM, or an account suddenly gaining admin privileges — Prootego flags it instantly and provides your security team with a correlated timeline of events, not just isolated alerts.

This approach dramatically reduces mean time to detect (MTTD) and mean time to respond (MTTR), turning months of undetected compromise into hours — or even minutes. Automated response playbooks can isolate a compromised endpoint, revoke stolen credentials, and block malicious IPs before an analyst even opens a ticket.

Don't wait until the damage is done. Book a free demo of Prootego XDR today and discover how proactive threat detection can protect your business from the compromises you don't yet know about.