How intelligent security detects abnormal email behavior

SIEM Use Cases for Email Exchange 📧 In the world of cybersecurity, email exchanges are a crucial battleground. Here are some SIEM use cases that play a vital role in fortifying your organization's email security: 👉Top 10 External Communicators: Identify the top users sending emails to external domains. Understanding this communication flow helps monitor external interactions effectively. 👉Email Activity Insights: Keep an eye on the top 10 email receivers and senders within your organization. This insight aids in understanding communication patterns and potential anomalies. 👉Data Leakage Identification: Utilize SIEM to detect data leakage through email channels. Ensure that sensitive information doesn't fall into the wrong hands. 👉Large File Monitoring: Track and manage large files sent via email. This helps in controlling data transfer sizes and ensuring compliance with security policies. 👉Malicious/Suspicious Attachments: Enhance your security posture by identifying and addressing emails with malicious or suspicious attachments promptly. 👉After-Hours Email Monitoring: Monitor emails going out from your company domain to other domains after office hours. This helps in identifying potential security risks during non-business hours. 👉Individual Email Bandwidth: Keep track of high email bandwidth utilization by individual users. Unusual spikes may indicate security threats or abnormal activities. 👉Undelivered Messages Detection: Detect undelivered messages promptly. This ensures that critical communications are not missed and addresses potential delivery issues. 👉Mailbox Security Incidents: Identify unauthorized access, such as mailbox access by another user or a user sending a message as another user. Strengthen your email security by detecting and responding to such incidents. 👉Login Anomalies: Detect users logging into mailboxes that are not their primary accounts. Unusual login patterns may signal compromised accounts. 👉Auto Redirected Mails: Stay vigilant for auto-redirected emails. Detect and prevent unauthorized forwarding of emails. 👉Internal Email Insights: Identify the top 10 users sending emails internally. This helps in understanding internal communication dynamics. 👉SMTP Gateway Monitoring: Monitor SMTP gateways for sudden spikes in incoming emails. Rapid increases may indicate potential security threats or attacks. 👉Rejected Mails Analysis: Keep an eye on a high number of rejected emails from a single "from" address. This helps in identifying and mitigating potential spam or phishing attempts. Utilize these SIEM use cases to strengthen your email security strategy and create a robust defense against evolving cyber threats.

🛡️ SOC Project: Phishing Email Detection Using Splunk 🚨 In the fight against cyber threats, email remains one of the most exploited vectors — and phishing is often the attacker’s first step. 🎯 As part of a hands-on SOC (Security Operations Center) project, I developed a phishing detection system using Splunk, targeting suspicious email content and attachments. 🔍 Key Highlights: ✅ Parsed email gateway logs (Exchange, Proofpoint) ✅ Detected phishing patterns using SPL (e.g., subject="*password*", attachment="*.exe") ✅ Created visual dashboards: 🚨 Suspicious Emails by Sender 📎 Suspicious Attachments (.exe) 📬 Phishing Email Subjects ✅ Integrated tools like VirusTotal, URLScan, and EmailRep for deeper investigation 💡 Demonstrated Skills: • SIEM log analysis • Email forensics • Regex-based detection • Threat hunting & reporting • Dashboarding with Splunk and Python (optional) 📊 This project not only strengthened my threat detection skills, but also taught me the value of proactive email defense in enterprise environments. 🔗 Want to see the full dashboard or walkthrough? Drop a comment or DM me. #CyberSecurity #SOCAnalyst #Splunk #PhishingDetection #SIEM #ThreatHunting #EmailSecurity #IncidentResponse #SOC #InfoSec #CyberDefense #SecurityOperations #SplunkDashboards #MalwareAnalysis #SecurityMonitoring #PhishingEmails #SOCProjects #SecurityTools #SecurityResearch #SecurityAnalytics #BlueTeam #Regex #SOCWorkflows #ThreatIntelligence #SecurityEngineer #EmailGateway #CyberSkills #NetworkSecurity #SOCPlaybook #PythonSecurity #SIEMTools #SOCTraining #SOCExperience #CybersecurityAwareness #DigitalForensics #SIEMUseCases #SecurityUseCases #SecurityAlerting #CyberThreats #MaliciousAttachments #SplunkSPL #SecurityDashboards #EmailThreats #InfosecCommunity #EndpointSecurity #MalwarePrevention #SplunkSecurity #ResumeProjects #EmailInvestigation #URLAnalysis #SecurityUseCaseDesign

𝐖𝐡𝐚𝐭’𝐬 𝐲𝐨𝐮𝐫 𝐟𝐢𝐫𝐬𝐭 𝐜𝐨𝐮𝐫𝐬𝐞 𝐨𝐟 𝐚𝐜𝐭𝐢𝐨𝐧 𝐚𝐬 𝐚 𝐒𝐎𝐂 𝐚𝐧𝐚𝐥𝐲𝐬𝐭 𝐢𝐟 𝐲𝐨𝐮 𝐬𝐞𝐞 𝐀𝐛𝐧𝐨𝐫𝐦𝐚𝐥 𝐍𝐮𝐦𝐛𝐞𝐫 𝐨𝐟 𝐄𝐦𝐚𝐢𝐥𝐬 𝐭𝐨 𝐈𝐧𝐯𝐚𝐥𝐢𝐝 𝐑𝐞𝐜𝐢𝐩𝐢𝐞𝐧𝐭𝐬? 𝘏𝘦𝘳𝘦'𝘴 𝘵𝘩𝘦 𝘬𝘦𝘺 𝘴𝘵𝘦𝘱𝘴 𝘵𝘰 𝘪𝘯𝘷𝘦𝘴𝘵𝘪𝘨𝘢𝘵𝘦: 𝐒𝐭𝐞𝐩-1: 𝐂𝐨𝐧𝐟𝐢𝐫𝐦𝐚𝐭𝐢𝐨𝐧 𝐨𝐟 𝐓𝐫𝐮𝐞 +𝐯𝐞 𝐨𝐫 𝐅𝐚𝐥𝐬𝐞 +𝐯𝐞 1. Check how common is this specific alert in your environment? 2. Bulk Email Campaigns: If your organization is running a large email marketing campaign, some emails might be sent to outdated or incorrect addresses, triggering the alert. 3. Automated Systems: Automated systems or applications that send emails might have outdated or incorrect recipient lists. 4. Testing and Development: During testing or development phases, developers might use invalid email addresses to test email functionalities. 5. Some users might have left the organization and their email account is disabled. This could lead to false positive as well. 6. Regular network scans or vulnerability assessments might trigger the same threat pattern, leading to false positives. 𝐒𝐭𝐞𝐩-2: 𝐈𝐟 𝐭𝐡𝐞 𝐢𝐧𝐜𝐢𝐝𝐞𝐧𝐭 𝐢𝐬 𝐜𝐨𝐧𝐟𝐢𝐫𝐦𝐞𝐝 𝐚𝐬 𝐓𝐫𝐮𝐞 +𝐯𝐞, 𝐭𝐡𝐞𝐧 𝐟𝐨𝐥𝐥𝐨𝐰 𝐭𝐡𝐞 𝐛𝐞𝐥𝐨𝐰 𝐬𝐭𝐞𝐩𝐬. 1. Perform a thorough investigation to determine the scope and impact of the incident. 2. Review the alert details in SIEM to understand the context, including the source IP, destination IP, and the time of the event. 3. Check the volume and frequency of the emails sent to invalid recipients. 4. Review email server/gateway logs to identify the source IP addresses, user accounts, and applications involved in sending the emails. 5. Look for patterns such as specific times, email subjects, or recipient domains that might indicate the nature of the issue. 6. Investigate if any systems or accounts have been compromised and are being used to send spam or phishing emails. 7. Look for other alerts that might be related to the same source username. This can help in understanding if the attack is part of a larger campaign. 8. Compare the current alert/scenario with historical data to identify any anomalies. 𝐋𝐨𝐠𝐬 𝐰𝐞 𝐧𝐞𝐞𝐝 𝐭𝐨 𝐜𝐡𝐞𝐜𝐤 𝐟𝐨𝐫 𝐬𝐮𝐜𝐡 𝐢𝐧𝐜𝐢𝐝𝐞𝐧𝐭𝐬: >> Email Server Logs: Show email details (sender, recipient, timestamps, errors) to identify invalid emails. >> Firewall Logs: Identify suspicious outbound traffic and unauthorized connections to the email server. >> IDS/IPS Logs: Detect and alert on suspicious activities like unusual logins or data exfiltration. >> Endpoint Security Logs: Provide device activity details, including malware detections and unauthorized access attempts. >> Authentication Logs: Identify compromised user accounts and unusual login patterns from systems like Active Directory. Feel free to share your thoughts—I’d love to hear them! #CyberSecurity #IncidentResponse #SOC #Phishing