Remote Email Collection
Remote Email Collection [T1114.002]
Information
Introduction
Remote Email Collection (T1114.002) is a sub-technique under the MITRE ATT&CK framework's Collection tactic. Attackers utilize this method to access and collect email messages from remote services or servers, often to harvest sensitive information, credentials, or confidential communications. By remotely accessing email accounts through various protocols, adversaries can silently extract critical information without the need for direct interaction with user endpoints.
Deep Dive Into Technique
Remote Email Collection involves adversaries remotely connecting to email services or servers to access and exfiltrate email data. Attackers typically leverage standard email protocols and methods to perform this collection, including:
IMAP (Internet Message Access Protocol):
Attackers authenticate to the IMAP server using compromised credentials.
IMAP provides full mailbox access, allowing attackers to read, delete, or move messages.
Attackers may use command-line tools or scripts to automate the extraction of email data.
POP3 (Post Office Protocol version 3):
Attackers authenticate to the POP3 server using valid credentials.
POP3 typically downloads emails to the client and deletes them from the server, but attackers may configure their tools to leave copies on the server to avoid suspicion.
Attackers often use automated scripts or specialized tools to quickly download large volumes of email messages.
Microsoft Exchange Web Services (EWS):
Attackers leverage compromised credentials to access Exchange servers via web services.
EWS provides robust access, including reading emails, calendars, contacts, and attachments.
Attackers may use tools such as MailSniper or custom scripts to automate extraction of email data through EWS.
Microsoft Graph API and OAuth-based Access:
Attackers may exploit OAuth tokens or compromised application credentials to access cloud-based email services (e.g., Microsoft 365, Google Workspace).
Using API calls, attackers can silently extract emails and attachments without triggering traditional authentication alerts.
Attackers frequently automate email extraction processes using custom scripts, command-line tools, or publicly available frameworks. Automation allows attackers to rapidly collect large volumes of data and minimize their exposure window.
When this Technique is Usually Used
Remote Email Collection typically occurs in various attack scenarios and stages, including:
Initial Reconnaissance and Information Gathering:
Adversaries may remotely collect email data to gather intelligence on targeted organizations, employees, or business operations.
Credential Theft and Reuse:
Attackers who have acquired valid email credentials through phishing campaigns, credential stuffing, or keylogging may remotely access email accounts to extract sensitive information.
Espionage and Persistent Access:
Nation-state actors or sophisticated threat groups often use remote email collection to silently monitor communications, gather intelligence, and maintain persistent visibility into targeted organizations.
Business Email Compromise (BEC) Attacks:
Attackers remotely access email accounts to monitor internal communications, impersonate employees, and conduct fraudulent activities such as invoice manipulation or wire fraud.
Post-Compromise Data Exfiltration:
After initial compromise of an organization's network or cloud environment, attackers may remotely access email servers or cloud services to extract sensitive communications and attachments.
How this Technique is Usually Detected
Detection of Remote Email Collection typically involves a combination of security monitoring, logging, and anomaly detection methods, including:
Authentication and Access Logs:
Monitoring login attempts and analyzing authentication logs for unusual access patterns, such as logins from unfamiliar locations, IP addresses, or at unusual times.
Protocol-Specific Logging and Monitoring:
IMAP, POP3, and EWS logs can indicate abnormal usage patterns, such as large-scale downloads or automated access patterns.
Monitoring API usage logs (e.g., Microsoft Graph API logs) for suspicious application access or unexpected OAuth token use.
Anomaly Detection and Behavioral Analytics:
Tools and SIEM solutions that leverage behavioral analytics can detect deviations from normal user behavior, such as mass email downloads, rapid mailbox access, or unusual client software usage.
Email Server and Cloud Security Tools:
Deploying specialized security solutions for email servers or cloud email services (e.g., Microsoft Defender for Office 365, Google Workspace Security Center) can help detect and alert on suspicious activities.
Indicators of Compromise (IoCs):
Unusual email client User-Agent strings or software used for mailbox access.
Suspicious IP addresses or geolocation anomalies in email authentication logs.
Sudden or unusual mailbox activity, such as mass email deletions or large-scale downloads.
Unexpected OAuth app installations or permissions granted to unknown third-party applications.
Why it is Important to Detect This Technique
Early detection of Remote Email Collection is crucial due to its significant potential impact on organizations, including:
Data Breach and Sensitive Information Exposure:
Attackers can gain access to confidential communications, trade secrets, intellectual property, or personally identifiable information (PII), leading to severe business and regulatory consequences.
Credential and Identity Theft:
Email accounts often contain password resets, multi-factor authentication codes, or other sensitive information, enabling further compromise of additional accounts or systems.
Financial Loss and Fraudulent Activities:
Attackers conducting BEC attacks or invoice fraud can cause significant financial damage by manipulating internal communications and payment processes.
Damage to Reputation and Trust:
Exposure of sensitive communications or customer data can severely impact an organization's reputation, eroding customer trust and confidence.
Compliance and Regulatory Violations:
Unauthorized access and exfiltration of email data may lead to violations of data protection regulations (e.g., GDPR, HIPAA), resulting in fines and legal consequences.
Early detection enables rapid containment and remediation, significantly reducing the overall impact and potential damage resulting from email data exfiltration.
Examples
Real-world examples of Remote Email Collection include:
APT28 (Fancy Bear):
APT28 leveraged spear-phishing campaigns to obtain valid email credentials, remotely accessing email accounts via IMAP to extract sensitive communications from targeted organizations, including political entities and government agencies.
APT33 (Elfin):
Iranian threat group APT33 used compromised credentials to remotely access email accounts via Outlook Web Access (OWA) and Exchange Web Services (EWS), extracting confidential communications from energy and aerospace-sector targets.
Cloud Hopper (APT10):
APT10 targeted managed service providers (MSPs) to gain access to customer email systems, remotely extracting email data using compromised credentials and automated scripts, resulting in significant intellectual property theft and espionage.
Business Email Compromise (BEC) Incidents:
Numerous documented BEC attacks involved attackers remotely accessing corporate email accounts, monitoring internal communications, and impersonating executives or suppliers to conduct invoice fraud and wire transfer scams.
OAuth-based Email Access (OAuth Phishing):
Attackers have leveraged OAuth phishing campaigns (e.g., OAuth consent attacks) to trick users into granting malicious third-party apps access to their email accounts, enabling attackers to silently extract emails via remote API calls.
These examples demonstrate the widespread use of Remote Email Collection across various threat actors, sectors, and attack scenarios, highlighting the importance of robust detection and prevention strategies.
Last updated
Was this helpful?