Critical Zoho Platform Updates December 2025: Security & API Changes You Can't Ignore

Immediate Platform Updates (Dec 10-21)

Zoho has rolled out several updates in the December 10-21 timeframe that impact how you sync files, respond to support tickets, and integrate with third-party systems. While some of these updates are feature enhancements, others involve critical security policy changes that require immediate attention.

WorkDrive TrueSync: Linux Desktop Support

Zoho WorkDrive TrueSync now officially supports Linux desktop environments, giving your sync-agent workflows equal footing across Windows, macOS, and Linux platforms.

What This Means for You

• Cross-Platform Parity: Ubuntu and Fedora desktop users can now use TrueSync just like Windows and macOS users
• Sync-Agent Workflows: File watchers, filesystem integrations, and endpoint sync operations now work seamlessly on Linux
• Developer-Friendly: Development teams using Linux workstations can sync files directly without workarounds
• Server Integration: Easier integration with Linux-based servers and automation scripts

Technical Details

The Linux TrueSync client supports:

• Real-time file synchronization
• Selective sync (choose which folders to sync locally)
• Team Folders collaboration
• Version history and conflict resolution
• Offline access to synced files

Zoho Desk: Mass-Reply & AI Enhancements

Zoho Desk December updates bring two major improvements for support teams: mass-reply templates with snippets and expanded Zia AI assistance inside tickets.

1. Mass-Reply Templates + Snippets

Support agents can now respond uniformly at scale when handling multiple tickets with similar issues. This is particularly useful for:

• Outage Communications: Send consistent updates to all affected customers
• Product Announcements: Reply to inquiries about new features with standardized responses
• Policy Changes: Ensure all customers receive accurate information
• Seasonal Responses: Holiday hours, shipping updates, or promotional information

2. Zia AI-Powered Assistance

Zia continues to expand inside tickets with three key capabilities:

• Ticket Summaries: Automatically generate concise summaries of long ticket threads
• Reply Help: Suggested responses based on ticket context and historical data
• Insights: Sentiment analysis, priority recommendations, and suggested tags

Platform & Automation Essentials

Several core platform features remain unchanged but are critical to understand for your integrations and automations:

Bulk Write Async Jobs in CRM

Core Bulk Write async jobs in Zoho CRM remain asynchronous and callback/status-driven. No changes in this release window, but here's what you need to know:

• Bulk operations continue to use callbacks for completion notifications
• Status checks remain the recommended method for monitoring long-running jobs
• No breaking changes to existing bulk write implementations
• Rate limits and quotas unchanged

Webhook HMAC Signing

Webhook HMAC signing practices remain in place for secure webhook verification. Important: Projects and Sign include HMAC headers that you should always validate in your webhook receivers.

// Example webhook validation (Node.js)
const crypto = require('crypto');

function validateWebhook(payload, signature, secret) {
    const hmac = crypto
        .createHmac('sha256', secret)
        .update(JSON.stringify(payload))
        .digest('hex');

    return hmac === signature;
}

// In your webhook handler
if (!validateWebhook(req.body, req.headers['x-zoho-signature'], SECRET)) {
    return res.status(401).send('Invalid signature');
}

Records Upsert Semantics

Records Upsert semantics haven't shifted in this brief release cycle. No breaking API behavior announcements in the December 10-21 window. Your existing upsert logic continues to work as expected.

Security-Critical Policy Shifts (Action Required)

This is where you need to pay close attention. Zoho is making two significant security-related changes that will impact how you authenticate API calls and manage OAuth connections.

OAuth Connector Deprecation: Dec 31 Deadline

Deadline: December 31, 2025

The default Zoho OAuth connector is being deprecated. After December 31, 2025, new OAuth connections will no longer appear in defaults and will need to be replaced with service-specific or custom connections for safe API authentication.

What's Changing

• Default OAuth Connector Removed: The generic "Zoho OAuth" connector will vanish from connection defaults
• Service-Specific Connections Required: You must create connections specific to each Zoho service (CRM, Books, Desk, etc.)
• Custom OAuth Apps Recommended: For production integrations, create custom OAuth clients in Zoho API Console
• Existing Connections Grandfathered: Connections created before Dec 31 will continue to work (for now), but updates recommended

Why This Matters

The default OAuth connector was convenient but posed security risks:

• Too broad in scope (access to all Zoho services)
• Harder to audit and monitor
• Violated principle of least privilege
• Difficult to revoke granular access

How to Migrate

1. Audit Your Connections: List all integrations using the default OAuth connector
2. Create Service-Specific Connections: In each Zoho app, go to Setup → Developer Space → Connections
3. Create Custom OAuth Clients: Visit Zoho API Console and create dedicated OAuth clients
4. Update Your Integrations: Replace default OAuth references with new service-specific connections
5. Test Thoroughly: Verify all integrations work with new connections before Dec 31

Deluge invokeURL Security Changes

Status: Already in Effect

Deluge's invokeURL deprecation of embedded credentials has already taken effect. You can no longer use inline authentication in invokeURL calls. You must now use Connections instead of inline auth for secure service calls.

What Changed

Previously, you could embed credentials directly in Deluge invokeURL calls like this:

// DEPRECATED - DO NOT USE
response = invokeurl
[
    url: "https://api.example.com/endpoint"
    type: GET
    parameters: {"username": "user@example.com", "password": "secretpass"}
];

Now you must use Connections:

// Create a Connection in Zoho first, then reference it
response = invokeurl
[
    url: "https://api.example.com/endpoint"
    type: GET
    connection: "your_connection_name"
];

Why This Change Was Made

• Security: Credentials embedded in code can be exposed through logs, error messages, or code exports
• Auditability: Connections provide clear audit trails of which integrations access which services
• Rotation: Update credentials in one place (Connection settings) rather than hunting through scripts
• Compliance: Meets security compliance requirements for credential management

How to Update Your Scripts

1. Identify Affected Scripts: Search your Deluge code for invokeURL calls with embedded credentials
2. Create Connections: For each external service, create a Connection in Zoho
3. Update invokeURL Calls: Replace credential parameters with connection references
4. Test Thoroughly: Verify all API calls work with the new Connection-based approach
5. Remove Old Credentials: Delete embedded credentials from your code

Your Action Items Checklist

Here's your prioritized action plan for these December updates:

Need Help with These Updates?

If you're feeling overwhelmed by these security changes or aren't sure where to start, we can help. ZMCOR specializes in Zoho integrations, API development, and platform migrations.

Services We Offer

• OAuth Migration: Audit and migrate from default OAuth to service-specific connections
• Deluge Script Updates: Convert embedded credentials to secure Connections
• Integration Testing: Comprehensive testing to ensure nothing breaks
• Documentation: Document your new connection architecture
• Training: Train your team on new security best practices

Stay Ahead of Zoho Updates

Zoho continues to evolve rapidly, with new features, security improvements, and platform changes announced regularly. December 2025's updates are particularly important because they involve breaking changes that require action.

The key takeaways:

• WorkDrive TrueSync now supports Linux - great for development teams
• Zoho Desk AI features continue to improve support efficiency
• OAuth connector deprecation requires migration by Dec 31
• Deluge embedded credentials are already deprecated - use Connections

Don't wait until the last minute. Start your migration planning today, test thoroughly, and ensure your integrations continue running smoothly into 2026.