Top Use Cases We Monitor in a SIEM


1. Unusual Authentication Activity
What to Monitor:
- Multiple failed login attempts (brute-force)
- Logins from new or geographically distant locations
- Privileged account logins outside business hours
Why It Matters: Attackers often brute-force credentials or use stolen passwords. Early detection prevents unauthorized access.
2. Privilege Escalation Attempts
What to Monitor:
- Creation or modification of admin accounts
- Changes to group memberships (e.g., adding users to Domain Admins)
- Use of sudo, runas, or other privilege elevation commands
Why It Matters: Privilege escalation is a key step in moving from entry point to full control. Detecting it stops attackers in their tracks.
3. Lateral Movement Indicators
What to Monitor:
- Remote execution tools (e.g., PsExec, WMI)
- SMB connections between unusual hosts
- Use of administrative shares (e.g., C$, ADMIN$)
Why It Matters: Once inside, attackers move laterally to access critical assets. Identifying this behavior quickly limits damage.
4. Data Exfiltration Patterns
What to Monitor:
- Large data transfers to external IPs
- Unusual use of FTP, SFTP, cloud storage uploads
- DNS tunneling or covert channels
Why It Matters: Exfiltration often signals a breach in progress. Rapid alerts mean you can interrupt data theft before it’s complete.
5. Malware & Ransomware Indicators
What to Monitor:
- Execution of known malicious hashes
- Rapid creation or encryption of files
- Suspicious PowerShell or script-based activity
Why It Matters: Immediate detection of malware behavior is crucial to contain outbreaks and prevent widespread impact.
6. Configuration Changes & Policy Violations
What to Monitor:
- Firewall rule modifications
- Changes to security group policies
- Disabled or altered logging settings
Why It Matters: Attackers often weaken defenses before launching an attack. Monitoring config changes ensures policies remain intact.
7. Anomalous User Behavior
What to Monitor:
- Access to systems or data outside a user’s normal role
- Bulk access or downloads of sensitive information
- Use of unusual command-line tools
Why It Matters: Insider threats or compromised accounts often exhibit behavior anomalies. Detecting these helps prevent insider-driven breaches.
Suitable For & Integration Tips
Suitable For:
- Organizations with diverse log sources (network, endpoints, cloud)
- Teams using SIEM for both security and compliance monitoring
Integration Tips:
- Correlate endpoint (EDR) and network logs for richer context
- Fine-tune thresholds to minimize false positives
- Align use cases with your incident response playbooks
At Cybersec.net, we help you define, implement, and fine-tune SIEM use cases—ensuring you catch the threats that matter and ignore the noise, all under strict NDA.
🔗 Related Resources:
- What Does a SIEM Actually See? (And What It Misses)
- EDR vs. SIEM vs. FIM — What’s the Difference?