Issue regarding files uploaded to the Channel Talk media server

We sincerely apologize to all customers affected by the file deletion issue. Below is the technical report outlining the details of the incident.


Summary

- Incident period: January 12, 2026 (Mon), 11:28 PM – January 13, 2026 (Tue), 12:43 AM (EST)
- Scope of impact: Media files (images, audio, attachments, etc.) stored in some channels

Cause and Impact

This incident was not caused by an external factor or system infrastructure failure, but by insufficient internal operational procedures and validation.

On January 13, 2026, during a scheduled cleanup of files that had reached their retention period, a code error resulted in files being deleted beyond the intended scope. The root cause was the lack of adequate pre-validation of the impact scope, insufficient verification of deletion targets, and the absence of safety mechanisms for recovery.

As a result, the following issues occurred:
- Silent audio in inbound call features (e.g., IVR and guidance messages) due to failed audio file references
- Inability to view files used in macros, profiles, cover images, and custom button images
- Inability to view files within one time message, campaigns, workflows, and ALF tasks
- Inability to view images and attachments in team chats and user chats

Actions Taken and Recovery Status
- Immediately halted the file deletion logic upon detection and rolled back the system to a previous stable version
- Temporarily disabled certain related features to prevent further impact
- Sequentially completed recovery of voice-related features, including TTS and IVR
- Provided and operated a dedicated guidance page allowing customers to review deleted files and re-register them as needed

Preventive Measures
To prevent similar incidents from recurring, we have immediately implemented the following measures:
- Mandatory pre-impact analysis and approval processes for all destructive actions, such as file deletion
- Introduction of pre-execution visualization and confirmation of deletion targets
- Implementation of a multi-approval–based operational policy

In addition, we will conduct a comprehensive review of our file management system and continue to improve our operational processes.

[Important] Apology and Action Plan Regarding Media File Deletion in Channel Talk

Dear Customers,
This is the Channel Team.

First and foremost, we would like to offer our deepest apologies to all our customers who trust and use our services.

On January 13, 2026, between 13:30 and 14:40 (KST), an issue occurred where media files (images, audio, attachments, etc.) stored in certain channels were deleted. This was due to insufficient verification and control procedures during an internal file deletion process.

We take the protection of our customers' valuable data as our highest priority, and we are deeply pained that such an incident has occurred. Our entire team takes full responsibility for this matter.

[Identified Issues and Scope of Impact]
Phenomenon: Inability to view, play, or download certain previously uploaded media files.
Scope:
1. Partial images and attachments in conversations (Team Chat, User Chat)
2. Images and attachments within Workflows, Macros, Marketing Campaigns, and ALF Tasks
3. Profile, Cover, and Custom Button images, etc.
※ Please note that critical data, including text messages, consultation history, and customer information, has NOT been deleted and remains securely stored and operational.

[Recovery Status and Requests]
We are currently mobilizing all available technical resources to attempt recovery. Further verification is required to determine the exact scope of the impact and the possibility of recovery. We plan to provide a more detailed update by tomorrow.
If you have files that are urgently needed for your business operations, we kindly ask you to re-upload them.
For any files that are confirmed to be recoverable, we will proceed with automatic recovery immediately without requiring separate requests from customers.

[Future Actions and Timeline]
We have activated a company-wide emergency response system.
-Jan 14, 2026: Announcement of the media file deletion incident
-Jan 15, 2026: Provision of a dedicated page to check the impact scope for each customer
-Jan 16 – 19, 2026: Additional recovery efforts and individual support for affected customers
-Jan 21 – 23, 2026: Sharing of a detailed technical report, including the root cause and recurrence prevention measures

All technical recovery measures are being prioritized. Once the scope of damage is clearly defined, we will promptly review and announce a compensation plan.

We consider this issue to be entirely our responsibility and sincerely apologize once again for the inconvenience and concern this has caused. We will take full responsibility and do our best to minimize the impact and prevent this from happening again.

Sincerely, Channel Team

We would like to inform you that an issue has been identified with some files uploaded to the Channel Talk media server. This issue has affected a limited number of channels.

Incident Period
- January 13, 2026, approximately 13:30 – 14:40 (KST)

While files uploaded after 14:40 (KST) are working as intended, features using files uploaded prior to this time may still experience issues.

Scope of Impact
- Workflows, Marketing, and ALF (Profile images, Tasks): Files such as images, videos, and PDFs used in these features may not be displayed correctly.
- Macros: If a macro contains uploaded images or files, the macro message may fail to send.
- Inbox/Team Chat: Files exchanged within these areas may not be displayed correctly.

Action Taken by Channel Team
- Marketing campaigns with affected files have been deactivated.
- We are currently investigating the possibility of recovering affected workflow files.

Recommended Immediate Action
- For currently affected items, you can restore normal operation immediately by re-uploading the files in their respective locations.
- We apologize for the inconvenience and kindly ask you to follow this method for a quick resolution while our team continues to work on a fundamental fix.

We are committed to resolving this issue as quickly as possible and will provide further updates as they become available.

Depending on the impact, we may issue additional notices or contact affected channels individually to minimize any further inconvenience.

If you need to check if your channel is affected or have any questions, please contact the Channel Team.

Temporary issue has been detected with Customer Support (Inbox) feature. We are currently investigating the cause and will provide updates shortly. We apologize for any inconvenience this may cause.