Detect Exfiltration Over Web Service in IBM QRadar
Adversaries may use an existing, legitimate external web service to exfiltrate data rather than their primary command and control channel. Popular web services acting as an exfiltration mechanism may give significant cover because hosts within a network are likely already communicating with them prior to compromise. Firewall rules may also already exist to permit traffic to these services. Web service providers commonly use SSL/TLS encryption, giving adversaries an added level of protection. Observed real-world abuse includes exfiltration to Telegram (Magic Hound, Contagious Interview), cloud storage (APT28 to Google Drive, Exbyte/BlackByte to Mega.co.nz), code repositories, file-sharing services (anonymfiles.com, file.io), and Microsoft Exchange Web Services (OilCheck, SampleCheck5000).
MITRE ATT&CK
- Tactic
- Exfiltration
- Technique
- T1567 Exfiltration Over Web Service
- Canonical reference
- https://attack.mitre.org/techniques/T1567/
QRadar Detection Query
SELECT
DATEFORMAT(starttime, 'yyyy-MM-dd HH:mm:ss') AS EventTime,
sourceip AS SourceIP,
username AS Username,
CATEGORYNAME(category) AS EventCategory,
"sourceprocessname" AS ProcessName,
"CommandLine" AS CommandLine,
destinationhostname AS DestinationHostname,
destinationip AS DestinationIP,
destinationport AS DestinationPort,
LONG("BytesSent") AS BytesSent,
CASE
WHEN destinationhostname MATCHES '(api\.telegram\.org)' THEN 'Messaging API - Telegram'
WHEN destinationhostname MATCHES '(discord\.com|discordapp\.com)' THEN 'Messaging API - Discord'
WHEN destinationhostname MATCHES '(mega\.co\.nz|mega\.nz|file\.io|transfer\.sh|gofile\.io|anonymfiles\.com|anonfiles\.com|ufile\.io|pixeldrain\.com)' THEN 'File Sharing Service'
WHEN destinationhostname MATCHES '(pastebin\.com|hastebin\.com|rentry\.co|paste\.ee|ghostbin\.com|privatbin\.net)' THEN 'Paste/Text Storage'
WHEN destinationhostname MATCHES '(ngrok\.io|ngrok-free\.app|serveo\.net)' THEN 'Tunnel Service'
WHEN destinationhostname MATCHES '(content\.dropboxapi\.com|api\.dropboxapi\.com)' THEN 'Cloud Storage - Dropbox'
WHEN destinationhostname MATCHES '(www\.googleapis\.com|drive\.google\.com|storage\.googleapis\.com)' THEN 'Cloud Storage - Google'
WHEN destinationhostname MATCHES '(graph\.microsoft\.com|onedrive\.live\.com)' THEN 'Cloud Storage - Microsoft'
WHEN destinationhostname MATCHES '(api\.github\.com|gitlab\.com|bitbucket\.org)' THEN 'Code Repository'
WHEN destinationhostname MATCHES '(s3\.amazonaws\.com)' THEN 'Cloud Storage - AWS S3'
ELSE 'Unknown'
END AS ExfilCategory
FROM events
WHERE
starttime > NOW() - 86400 SECONDS
AND (
destinationhostname MATCHES '(api\.telegram\.org|discord\.com|discordapp\.com|mega\.co\.nz|mega\.nz|file\.io|transfer\.sh|gofile\.io|anonymfiles\.com|anonfiles\.com|ufile\.io|pixeldrain\.com|pastebin\.com|hastebin\.com|rentry\.co|paste\.ee|ghostbin\.com|privatbin\.net|ngrok\.io|ngrok-free\.app|serveo\.net|content\.dropboxapi\.com|api\.dropboxapi\.com|www\.googleapis\.com|drive\.google\.com|graph\.microsoft\.com|onedrive\.live\.com|api\.github\.com|gitlab\.com|bitbucket\.org|s3\.amazonaws\.com|storage\.googleapis\.com)'
OR (
"sourceprocessname" IMATCHES '(curl|wget|powershell|pwsh|python|node|wscript|cscript|certutil|bitsadmin)'
AND LONG("BytesSent") > 1048576
)
)
ORDER BY starttime DESCQRadar AQL detection for T1567 exfiltration over web services. Queries network flow and endpoint events to identify connections from scripting/transfer utilities to known file-sharing, messaging, cloud storage, and tunnel services. Flags both domain-matched connections and high-volume (>1MB) transfers from LOLBin processes to any external destination.
Data Sources
Required Tables
False Positives & Tuning
- Authorized DevOps pipelines using curl or Python to push build artifacts to AWS S3 or Google Cloud Storage
- Employees legitimately sharing large files via sanctioned OneDrive or Dropbox corporate accounts as part of normal business workflows
- Security operations tooling (e.g., SOAR playbooks, threat intel scripts) that upload indicators or reports to external sharing platforms
Other platforms for T1567
Testing Methodology
Validate this detection against 4 adversary techniques from Atomic Red Team. Each test below lists the behaviour to exercise and the telemetry you should expect to see. Executable commands and cleanup steps are available with Pro.
- Test 1Exfiltrate file via Telegram Bot API (curl)
Expected signal: Sysmon Event ID 1: Process Create with Image=curl.exe, CommandLine containing 'api.telegram.org' and 'sendDocument'. Sysmon Event ID 3: Network Connection to api.telegram.org:443 (resolves to Telegram's IP range). Sysmon Event ID 11: File Create for exfil-test.txt in %TEMP%.
- Test 2Upload staged archive to file-sharing service (file.io)
Expected signal: Sysmon for Linux (if deployed) Event ID 11: File Create for exfil-staging.tar.gz in /tmp. Sysmon Event ID 3: Network connection to file.io:443. Auditd syscall events for open/write (archive creation) and connect (curl network call). Process accounting records for tar and curl executions.
- Test 3Exfiltrate data via Discord webhook (PowerShell)
Expected signal: Sysmon Event ID 1: Process Create with Image=powershell.exe, CommandLine containing 'discord.com/api/webhooks' and 'Invoke-RestMethod'. Sysmon Event ID 3: Network Connection to discord.com:443 from powershell.exe. PowerShell ScriptBlock Log Event ID 4104 with the full webhook POST script including the URL and payload body.
- Test 4Bulk data upload to cloud storage via Python requests (Google Drive simulation)
Expected signal: Sysmon Event ID 1: Process Create with Image=python.exe, CommandLine containing 'googleapis.com' and '/upload/drive/v3'. Sysmon Event ID 3: Network Connection to www.googleapis.com:443 from python.exe. BytesSent will reflect the ~51KB payload even on 401 response (data is transmitted before auth rejection). Security Event ID 4688 if command line auditing enabled.
References (10)
- https://attack.mitre.org/techniques/T1567/
- https://blog.google/threat-analysis-group/iran-based-threats/
- https://www.welivesecurity.com/en/eset-research/oilrig-campaigns-2022-2023/
- https://www.trendmicro.com/en_us/research/20/l/pawn-storm-lack-of-sophistication-as-a-strategy.html
- https://www.bleepingcomputer.com/news/security/molerats-hackers-hide-new-espionage-attacks-behind-dropbox-and-facebook/
- https://symantec-enterprise-blogs.security.com/threat-intelligence/blackbyte-exbyte-ransomware
- https://www.microsoft.com/security/blog/2023/03/02/blackbyte-ransomware-group-reemerges-with-updated-tactics/
- https://learn.microsoft.com/en-us/defender-endpoint/advanced-hunting-devicenetworkevents-table
- https://github.com/redcanaryco/atomic-red-team/blob/master/atomics/T1567/T1567.md
- https://www.malwarebytes.com/blog/news/2020/02/ngrok-abused-by-hackers-to-host-phishing-sites-and-for-data-exfiltration
Unlock Pro Content
Get the full detection package for T1567 including response playbook, investigation guide, and atomic red team tests.