Who Is Exploiting GenAI Tools to Create Weaponized PDFs and Documents?

Table of Contents

• Introduction
• From Malicious Macros to Intelligent Documents
• The Convergence of Opportunity: Why GenAI Document Attacks Are Surging
• The GenAI-Powered Document Weaponization Chain
• Threat Actor Profile: Key Groups Weaponizing GenAI Documents
• Why Traditional Document Security Is Failing
• The Defensive Counterpart: AI-Based Content Disarm & Reconstruction (CDR)
• Building a Defense Against Intelligent Documents
• Conclusion
• FAQ

Introduction

For decades, the PDF or Word document has been the Trojan Horse of choice for cybercriminals. A seemingly harmless invoice, resume, or report arrives in an inbox, carrying a hidden malicious payload. But what we are seeing in 2025 is a terrifying evolution of this tactic. Threat actors are now leveraging powerful Generative AI models to craft weaponized documents that are not only technically evasive but also psychologically flawless social engineering tools. These intelligent documents are perfectly written, contextually relevant, and designed to disarm even the most cautious user. This leads us to a critical question for security professionals today: Who is exploiting GenAI tools to create these weaponized PDFs and documents, and what are their motives?

From Malicious Macros to Intelligent Documents

The classic malicious document was often easy to spot. It relied on a simple macro, was frequently riddled with spelling errors, and used generic, unconvincing lures. Security solutions and user awareness campaigns have become adept at catching these. The GenAI-powered document is a different beast entirely. It leverages AI to generate perfectly written, highly convincing content tailored to its specific target. More dangerously, it uses AI to generate polymorphic script—malicious code that is unique in every single document, rendering signature-based antivirus detection completely obsolete.

The Convergence of Opportunity: Why GenAI Document Attacks Are Surging

This new attack vector has exploded in popularity in mid-2025 for several key reasons:

• Ubiquitous GenAI APIs: The widespread availability of powerful large language models (LLMs) via APIs allows any threat actor, regardless of their own sophistication, to generate flawless text and code.
• Bypassing Human Scrutiny: The quality of the AI-generated content (e.g., a fake legal subpoena or a detailed project proposal) bypasses the natural human suspicion that typos and poor grammar used to trigger.
• Evading Static Analysis: Because the malicious script embedded in each document is algorithmically unique, it has no known signature for legacy antivirus scanners to detect.
• The Trustworthiness of Documents: Despite the risks, documents remain a fundamental and trusted part of business workflows, making them an ideal delivery mechanism for malware.

The GenAI-Powered Document Weaponization Chain

Creating these intelligent documents is a multi-stage process, fully automated by the attackers:

• 1. AI-Driven Reconnaissance: An AI agent scans public sources like LinkedIn, company websites, and social media to gather context about a target organization or individual.
• 2. Context-Aware Content Generation: Using the gathered intel, a GenAI model writes a highly convincing document. For example, it might create a fake RFQ (Request for Quotation) that references real projects mentioned on the target company's blog.
• 3. Polymorphic Payload Generation: A separate AI model generates a unique, obfuscated script (e.g., PowerShell, VBScript) for each document. This script is designed to be the initial dropper for more advanced malware.
• 4. Automated Delivery & Social Engineering: The weaponized document is attached to an equally well-crafted email, also written by AI, and sent to the target, completing the sophisticated social engineering lure.

Threat Actor Profile: Key Groups Weaponizing GenAI Documents

While this technology is accessible to many, our analysis shows three distinct categories of threat actors are leading its adoption:

Why Traditional Document Security Is Failing

Legacy security tools are struggling to cope with this new threat for several reasons:

• Signature-Based AV is Blind: As each malicious script is unique, there is no signature to match.
• Simple Sandboxing is Ineffective: Some AI-generated scripts are "environment-aware" and will not execute their malicious functions if they detect they are inside a generic sandbox environment.
• Human Training Has Limits: When a document is perfectly written and contextually relevant to your job, the traditional advice to "look for typos" is no longer applicable.
• Content Filtering Fails: The lure document itself is benign and well-written. Keyword-based content filters have nothing to flag.

The Defensive Counterpart: AI-Based Content Disarm & Reconstruction (CDR)

To combat AI-generated threats, a new generation of AI-powered defense is required. The leading technology in this space is Content Disarm and Reconstruction (CDR).

Instead of trying to *detect* malice, CDR assumes all documents from untrusted sources are potentially malicious. The process works as follows:

1. Deconstruction: The CDR engine breaks the incoming document down into its fundamental components (text, images, embedded files, scripts).
2. Filtering & Sanitization: It discards any active or potentially malicious components, like macros, scripts, and hyperlinks, based on a strict policy.
3. Reconstruction: The engine rebuilds a brand new, perfectly safe version of the document from only the sanitized components.

The user receives a fully functional, safe document, with any malicious elements having been surgically removed without relying on detection.

Building a Defense Against Intelligent Documents

A multi-layered defense is essential to protect against this vector:

• Deploy Advanced Email Security with CDR: This is the most effective technical control. Ensure your email gateway has a modern CDR capability to sanitize all incoming attachments.
• Disable Macros by Default: Use Group Policy to disable all macros from running in Office documents that originate from the internet.
• Train for Context, Not Just Content: Educate users to be suspicious of the *context* of a request. They should ask, "Was I expecting this invoice? Is this a normal way for my CEO to ask for this?" and verify via a separate channel.
• Implement Browser Isolation: Use browser isolation technology to open documents from untrusted sources in a remote, disposable container, preventing any malicious code from reaching the user's endpoint.

Conclusion

The humble document has been transformed by Generative AI into one of the most effective and insidious attack vectors of 2025. Financially motivated criminals, espionage groups, and state-sponsored actors are all leveraging this technology to bypass traditional defenses and human intuition. The fight against these intelligent documents cannot be won with legacy tools. It requires a zero-trust mindset—assuming any document can be hostile—and the adoption of modern, AI-powered defenses like Content Disarm and Reconstruction that focus on proactive sanitization rather than reactive detection.

FAQ

What is a "weaponized document"?

It is a seemingly harmless document file (like a PDF, Word doc, or Excel sheet) that contains a hidden malicious payload, such as a script or macro, designed to compromise the recipient's computer.

How does Generative AI make these documents more dangerous?

GenAI is used for two things: 1) To write perfectly worded, contextually relevant lure documents that trick users. 2) To generate unique, polymorphic malicious code for each document, making it invisible to traditional antivirus scanners.

What is polymorphic malware?

It's malware that can automatically change its own code. Because its "signature" is always different, it's extremely difficult for signature-based security tools to detect.

Who are the main actors using this technique?

Our intelligence points to three main groups: financially motivated cybercrime syndicates (like FIN7), industrial espionage groups, and state-sponsored espionage actors (like Russia's APT29).

Can you get hacked just by opening a PDF?

Yes. PDFs can contain scripts (like JavaScript) or exploit vulnerabilities in PDF reader software. While modern readers have improved security, a sophisticated, weaponized PDF can still lead to a compromise.

What is Content Disarm and Reconstruction (CDR)?

CDR is a security technology that proactively cleans documents. It deconstructs a file, removes any potentially malicious active content, and then reconstructs a perfectly safe, clean version for the user to open.

Is CDR better than a sandbox?

They serve different purposes, but CDR is often more effective for documents. Sandboxing observes a file to see if it does something bad, but advanced malware can detect a sandbox and remain dormant. CDR doesn't try to detect; it simply removes all active components by default.

My company's antivirus is up to date. Am I safe?

Not necessarily. Traditional antivirus relies on known signatures. Since GenAI can create a unique malware signature for every document, legacy AV is likely to miss it.

How can I spot an AI-generated malicious document?

It is extremely difficult. Since the content is flawless, you must focus on context. Ask yourself: "Was I expecting this document? Is this a normal business process? Does the request seem unusual?" When in doubt, verify with the sender through a different communication channel (like a phone call).

Are macros the only way documents can be malicious?

No. Documents can also contain embedded objects (OLEs), exploit software vulnerabilities in the reader application (e.g., Adobe Reader, Microsoft Word), or use malicious hyperlinks.

What is a "dropper"?

A dropper is a small piece of malicious code whose only job is to get past initial defenses and then "drop" or download a more powerful, full-featured piece of malware (like a banking trojan or ransomware) onto the victim's system.

Why are finance departments a common target?

Finance departments constantly deal with external documents like invoices and purchase orders, making them a high-probability target. A successful attack can lead directly to financial fraud or ransomware deployment.

What is industrial espionage?

It is the act of spying or using illicit means to gather trade secrets, intellectual property, or other confidential information from a competing company or nation for commercial advantage.

Does a password-protected document offer any security?

Password protection on a document only encrypts the content. It does not prevent a malicious script embedded within it from running once the document is opened by an authorized user.

What is browser isolation?

It's a security technology that executes all web Browse activity in a remote, isolated environment (either in the cloud or on a local server). If a user clicks a link to a malicious document, it opens in the isolated container, and no malicious code ever reaches the user's actual computer.

Should I disable JavaScript in my PDF reader?

Yes, for most users, disabling JavaScript in your PDF reader (like Adobe Acrobat) is a recommended security hardening step, as it's a common vector for exploits.

Are cloud-based document editors like Google Docs safer?

Generally, yes. Opening a document in a cloud-based editor like Google Docs or Office 365's web version is safer than opening it in a desktop application because the code is executed on Google's or Microsoft's servers, not your local machine.

What is an "environment-aware" script?

It's a sophisticated malicious script that first checks what kind of system it is running on. If it detects signs of a virtual machine or a known analysis sandbox, it will not execute its malicious payload, thereby evading detection.

Why target diplomats and NGOs?

State-sponsored groups target diplomats and NGOs to gather intelligence on foreign policy, political strategy, and sensitive negotiations, giving their government a strategic advantage.

What's the single most important takeaway?

Adopt a "zero trust" approach to documents. Don't trust any document from an external source, regardless of how well-written or convincing it seems. Use technical controls like CDR and train users to verify requests out-of-band.