Email attachments, files downloaded from the Internet, documents exchanged with partners – all of these are a daily part of work in an organization. At the same time, it is files that are one of the most commonly used malware vehicles. Macros in Office documents, infected PDFs, ZIP archives with hidden malware or files with zero-day exploits can bypass traditional protections. That’s why protecting against threats hidden in attachments requires a multi-layered approach, which solutions offer OPSWAT.
Key findings
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Attachments are one of the main attack vectors in organizations
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Classic antivirus scan does not detect all threats
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Files may contain hidden macros, exploits and malicious scripts
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OPSWAT uses multi-engine scanning and deep file analysis
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Content inspection and file reconstruction minimize risk
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Central policy management increases control over file transfers
Table of contents
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Why attachments are so dangerous
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The most common threats hidden in files
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Limitations of traditional antivirus solutions
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How file protection works with OPSWAT
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Reconstruction and decontamination of files (CDR)
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FAQ
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Summary
Why attachments are so dangerous
Attackers take advantage of the fact that users regularly open files received by e-mail or downloaded from external sources. The message may look plausible and the attachment may look like a simple PDF document or Excel sheet. In reality, the file may contain hidden code that, when opened, runs malware.
Significantly, many attacks no longer rely on simple malware, but on exploiting vulnerabilities in software or social engineering.
The most common threats hidden in files
Files may include:
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macros in Office documents
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malicious JavaScript scripts
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exploits that take advantage of application vulnerabilities
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encrypted malware payloads
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hidden elements in multilayer archives
Increasingly, threats are specifically crafted to bypass a single anti-virus engine.
Limitations of traditional antivirus solutions
Classic antivirus systems are mainly based on:
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signature databases of known threats
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simple heuristic analyses
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file reputation
The problem is that new malware variants and zero-day attacks may not yet be in the signature databases. As a result, a single AV engine may not detect the threat.
How file protection works with OPSWAT
Solutions offered by OPSWAT use a multi-layer approach that includes:
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multi-scanning (multi-motor virus scanning)
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deep analysis of file structure
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decoding of archives and containers
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sandboxing of suspicious content
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integrity checks and digital signatures
By using multiple detection engines simultaneously, the effectiveness of threat detection increases significantly.
Reconstruction and decontamination of files (CDR)
One of the most effective protection mechanisms is CDR (Content Disarm and Reconstruction) technology. It consists of:
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removing active elements from the file (macros, scripts)
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rebuilding a secure version of the document
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providing the user with a “cleaned” file
This approach eliminates the risk, even if the threat has not yet been identified as known malware.
FAQ
Is a single antivirus enough to protect attachments?
No – advanced threats can bypass a single detection engine.
Does the CDR change the content of the document?
The technology removes active elements, preserving the content of the document in a secure form.
Should attachment protection cover all channels?
Yes – e-mail, file transfer, data sharing portals and sharing systems should be covered by a consistent policy.
Summary
Attachments remain one of the most common vehicles for cyberattacks. Traditional antivirus solutions are not sufficient in the face of modern threats and security evasion techniques. The multi-layered approach offered by OPSWAT, which includes multi-scanning, sandboxing and CDR technology, effectively eliminates threats hidden in files. With centralized policy management and full transfer visibility, organizations can significantly reduce the risk of attachment incidents.
