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ClamAV guide

What is ClamAV used for?

ClamAV is an open-source malware scanning toolkit. It is most useful where files need to be checked locally, repeatedly or as part of a server, gateway or storage workflow.

Common ClamAV use cases

Email gateways

Scan incoming and outgoing attachments before messages reach a mailbox.

File uploads

Check files submitted to websites, portals and business applications.

Servers and NAS

Run scheduled or on-demand scans across selected server and storage locations.

Repair and triage

Add an independent file-scanning engine to a controlled diagnostic workflow.

Email and attachment scanning

Email gateways were ClamAV's original use case and remain a natural fit. A mail system can pass attachments to clamd or the scanning library before delivery. This helps catch known malicious documents, archives and executables centrally instead of relying entirely on every recipient device.

Scanning web and application uploads

Applications that accept documents, images, archives or software can scan a private temporary copy before making it available to other users. The safe pattern is to limit size and nesting, keep untrusted files outside executable locations, scan with a current engine and definitions, and treat scan errors or timeouts as failures rather than clean results.

Linux servers and file storage

Administrators use ClamAV for scheduled checks of upload areas, shared storage and files crossing trust boundaries. clamscan suits bounded jobs, whileclamd avoids repeatedly loading the engine for frequent scanning. FreshClam maintains signed malware databases. Linux also has an official on-access option, although deployment and permissions require care.

NAS and shared-folder scanning

A NAS stores files used by many devices, so a local scan can provide another point of inspection without sending customer data to a cloud scanning service. Administrators should select existing shares explicitly and start with read-only access. Unreadable content must produce a partial result, and remediation must require confirmation.

Chowder for Synology DSM packages its interface, ClamAV, FreshClam configuration and initial definitions together. The currently published build is for tested x86_64 systems only.

Why Windows is not a Chowder launch target

Windows includes Microsoft Defender. Chowder therefore concentrates its launch work on Linux and Synology rather than selling a second Windows scanner. ClamAV itself remains cross-platform, but no Windows Chowder download or paid plan is offered at launch.

Repair desks and refurbishment

Technicians can use ClamAV when examining customer files or preparing reused systems. A trustworthy workflow records what was scanned, what could not be read, which definitions were available and whether the job finished or was cancelled. Detection is evidence for review—not permission to delete customer data automatically.

Formats and content ClamAV can inspect

ClamAV recognises many archives, mail containers, documents and executable formats. See the official file-type listand project introduction. Format support, signatures and engine limits change over time, so production integrations should track supported releases and inspect the scanner's actual result codes.

Where ClamAV does not fit by itself

  • It does not replace operating-system updates, least privilege or secure backups.
  • It is not a full endpoint detection and response platform.
  • It cannot declare files clean when permissions, limits or cancellation prevented inspection.
  • It should not silently delete, move or quarantine customer files.
  • Old definitions or an unavailable engine must be shown as degraded or unavailable.

Use ClamAV with a clear workflow

Chowder turns those principles into a graphical scanner for Linux x64 and Synology DSM. Read the history of ClamAV, compare Chowder features, or visit Downloads.