Malware and Virus Scanner: automatically block infected file attachments in CometChat

CometChat's Malware and Virus Scanner automatically scans file attachments for malware and viruses before delivery, blocking infected files before they reach the recipient.

It is a default rule in CometChat's AI Moderation system. Toggle it on in the Dashboard and it applies immediately to all messages. No code changes required in the UI Kit or SDK.

What are we launching?

We are launching the Malware and Virus Scanner as a default moderation rule in CometChat, available for file attachments, images, videos, and audio files.

The scanner detects:

For file attachments specifically, supported file types include:

The rule is pre-configured and ready to use. It requires no additional code in your UI Kit or SDK integration.

Why does this matter to me as a developer?

When your app supports file sharing, every attachment is a potential vector for malicious content. An infected PDF or a zipped trojan sent through your chat can affect every recipient, and the responsibility for catching it sits with the platform.

Building your own file scanning pipeline means maintaining virus definition databases, managing scanning infrastructure, blocking delivery on detection, and keeping up with evolving threat signatures. That is significant engineering work that has nothing to do with your core product.

The Malware and Virus Scanner handles all of that automatically, before delivery, with a single toggle.

For healthcare, finance, and enterprise apps where compliance requirements mandate file scanning, this is an essential control. For any app that supports file sharing, it is a meaningful layer of protection with zero engineering cost to enable.

Key features and capabilities

Scans before delivery

The scanner runs before the file reaches the recipient. If an infected file is detected, it is blocked and never delivered. Users are protected without any manual intervention.

Covers all common file types

The rule covers the full range of attachment types that users commonly share:

Available across all media types

The Malware and Virus Scanner is not limited to file attachments. The same rule is available for:

This gives you consistent malware protection across every type of content shared in your app.

Configurable actions

When an infected file is detected, you choose what happens:

Block is the appropriate default for malware. Flag is available if you prefer to route detections to a manual review queue before taking action.

Filters for targeted application

Filters let you control which messages the rule applies to, based on sender or receiver attributes:

This means you can apply the scanner to specific user roles, specific groups, or specific tag combinations if your use case requires more granular control.

What is interesting about the tech behind this?

Deterministic detection, not AI confidence scoring

Unlike AI-based moderation rules that require a confidence threshold to be tuned, the Malware and Virus Scanner uses deterministic virus detection. There is no confidence percentage to set. Either a file contains a known threat signature or it does not. This makes it a reliable baseline rule to enable without any calibration.

No code change required

The rule is configured entirely in the CometChat Dashboard. Once enabled, it is automatically applied to all messages processed through CometChat. The UI Kit and SDK handle moderation seamlessly.

Recommended for compliance environments

The documentation explicitly recommends the Malware and Virus Scanner as an essential rule for healthcare, finance, and enterprise apps. It is the only file-specific rule listed as essential across all three of those use cases.

Reference links

Documentation: https://www.cometchat.com/docs/moderation/rules-management#file-rules

Rules Management documentation: https://www.cometchat.com/docs/moderation/rules-management

Blocked Messages: https://www.cometchat.com/docs/moderation/blocked-messages

Flagged Messages: https://www.cometchat.com/docs/moderation/flagged-messages

Moderation APIs: https://www.cometchat.com/docs/rest-api/moderation

Nivedita Bharathy

Product Marketing Specialist , CometChat

Nivedita Bharathy is a Product Marketing Specialist at CometChat with experience spanning AI startups, incubators, and enterprise SaaS. A Boston University graduate and avid reader, she specializes in transforming complex technology into compelling narratives that resonate with both technical and business audiences.