When people share files through your links, you don’t want malware coming along. FileGrab automatically scans supported executable uploads under 500 MB for known threats.
Why File Scanning Matters
File sharing links are collaborative. Anyone with the link can upload. That convenience creates risk if someone uploads something malicious.
Threats include:
- Viruses and trojans
- Ransomware
- Spyware
- Infected documents (macro malware)
Without scanning, malicious files spread through shared links.
How FileGrab Scans Files
FileGrab sends supported executable files under 500 MB to ClamAV, an open-source antivirus engine. The extension check examines every extension segment after the filename stem, so a disguised name such as document.pdf.exe is still treated as executable content.
The process:
- File uploads to FileGrab
- A scan job is submitted to ClamAV
- The result is recorded as clean, infected, skipped, or error
- Files detected as infected are quarantined
Scanning happens automatically. You don’t need to do anything.
What Gets Scanned
Scanning currently covers configured executable extensions such as .exe, .dll, .msi, .bat, .sh, and .dmg when the file is no larger than 500 MB. Files outside that extension list are not sent through this ClamAV flow. Larger executable files are marked skipped, and a failed scan is recorded as an error rather than represented as clean.
PDF, Office, archive, image, video, and audio content is not comprehensively scanned by this executable-focused control. Treat unfamiliar files cautiously regardless of file type.
What Happens When Malware Is Found
If a file triggers detection:
- The file is quarantined: Non-owners cannot download it from the shared link
- The owner is notified: The notification identifies the file and detected threat
- Owner access is warned: The owner may still download the quarantined file with a warning
- Bulk downloads exclude it: ZIP downloads omit quarantined files for non-owners
False positives occasionally happen. If you believe a file was incorrectly flagged, contact support with details.
Limitations of Scanning
Antivirus scanning catches known threats. It’s not perfect.
What scanning handles well:
- Known viruses and malware
- Common threat patterns
- Infected documents with known signatures
What scanning can’t catch:
- Brand new, unknown malware (zero-day)
- Sophisticated targeted attacks
- Social engineering (phishing links in documents)
- Unsupported file types or supported executable files over 500 MB
- Threats when a scan fails before a clean result is recorded
Scanning is one layer of protection, not complete security.
Best Practices for Link Owners
Know Who’s Uploading
Collaborative links are powerful but require trust. Share links with people you expect to upload, not publicly.
Check Unfamiliar Files
Even if scanning passes, be cautious with files from unknown sources. Open in isolated environments if unsure.
Use Password Protection
Password-protected links limit who can access and upload. Only people with the password can contribute.
Monitor Your Links
Check what’s been uploaded to collaborative links. FileGrab shows upload history.
Best Practices for Recipients
Recipients do not need an account or local scanning software to benefit when FileGrab detects and quarantines a supported executable. This is an additional layer, not a promise that every file is safe.
Download from Trusted Links
Only download from links you expected to receive. Unexpected file sharing links could be phishing.
Verify Before Opening
Even scanned files deserve scrutiny:
- Does the filename match what you expected?
- Does the sender know you’re downloading?
- Is the file type appropriate for the content?
Keep Your System Updated
Local antivirus provides another scanning layer. Keep it current.
Transparency in Security
FileGrab uses ClamAV because it’s:
- Open source: Code is publicly auditable
- Widely used: Signatures are updated constantly
- Proven: Decades of deployment in production systems
The scanner is intentionally focused on executable extensions, including disguised multi-extension filenames. FileGrab publishes these limits so users can make informed decisions instead of treating a clean or unscanned file as a guarantee.
The Bottom Line
Executable scanning adds a safety layer to collaborative sharing. FileGrab automatically submits supported executable files under 500 MB and quarantines files when ClamAV reports a known threat.
It’s not a replacement for security awareness, but it catches the obvious threats so you can focus on the edge cases that require human judgment.
Try FileGrab - File sharing with executable malware scanning as one layer of protection.