What is an Orphaned VBA Project in Phishing?

An orphaned VBA project refers to VBA code remnants in files, often overlooked by security tools, that adversaries leverage in phishing campaigns.

Why It Matters

Orphaned VBA projects present a unique vector in phishing attacks, particularly appealing to attackers for their ability to hide in plain sight. These projects are macros embedded within document files that may not typically associate with scripts, like DWG files. Their inconspicuous nature means they frequently evade stringent security measures, allowing malicious payloads to be delivered with lower detection rates.

For phishing operators, leveraging orphaned VBA projects can be a pathway to initiate attacks on unsuspecting users who view files as benign. From an operational perspective, this tactic enhances the likelihood of bypassing email filtering and endpoint security applications that are otherwise vigilant against macros in more traditional document types like Word or Excel.

In Practice

Imagine receiving an email from support@contractorupdate.com with the subject line “Latest CAD Blueprints for Review”. Inside the email, a message reads, “Dear team, please see attached the latest version of our project blueprints. Let us know if there are any changes needed.” The attached DWG file includes an orphaned VBA project that triggers when the file is opened, silently running code that downloads a malicious payload from a disguised domain.

In another scenario, an operator might intercept internal communications from a compromised account and send customized DWG files with hidden VBA scripts. This is presented as a routine file exchange — for example, an email to engineering@firmx.com states: “Please find the updated workflow diagrams attached for our quarterly report.” Without visible marks of malicious intent, the VBA script within deploys during the document’s opening, establishing a backdoor for future infiltration.

Operators using phishing lures have also begun to attach these orphaned VBA projects to compressed archive files, such as ZIPs, titled “HR_Updates_2023.zip”, claiming to be employee policy updates. Once decompressed and opened, these files’ VBA components can execute commands that exfiltrate data or gather credentials, all under the guise of standard workplace document management.

Related Terms

Understanding orphaned VBA projects within phishing architectures also requires familiarity with macro-based attacks, which rely on executing powerful scripts within legitimate office file types. Additionally, exploring fileless malware helps elucidate techniques where memory-only attacks evade traditional detection, and examining phishing kits reveals how attackers streamline their social engineering campaigns, often integrating emergent tactics like orphaned VBA projects into broader threat landscapes.

References

For an extensive dive into the implications and technical workings of orphaned VBA projects, see the analysis at ISC SANS. Additionally, explore how these phishing techniques evolve by visiting FireEye Threat Intelligence, which provides detailed reports on malware trends and phishing evolution.