CVE-2026-1895
📋 TL;DR
CVE-2026-1895 is an improper access control vulnerability in WeKan's attachment storage handler that allows remote attackers to bypass intended restrictions. This affects WeKan versions up to 8.20, potentially enabling unauthorized access to or manipulation of attachments. Organizations using vulnerable WeKan instances for project management or collaboration are at risk.
💻 Affected Systems
- WeKan
📦 What is this software?
Wekan by Wekan Project
⚠️ Risk & Real-World Impact
Worst Case
Attackers could access, modify, or delete sensitive attachments across all boards and lists, potentially exposing confidential data or disrupting business operations.
Likely Case
Unauthorized access to attachments within boards where the attacker has some level of access, leading to data exposure or integrity issues.
If Mitigated
With proper network segmentation and authentication controls, impact would be limited to authorized users within their designated access scope.
🎯 Exploit Status
The vulnerability requires some level of access to WeKan but can be exploited remotely. The specific manipulation technique is not publicly documented.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 8.21
Vendor Advisory: https://github.com/wekan/wekan/releases/tag/v8.21
Restart Required: Yes
Instructions:
1. Backup your WeKan data and configuration
2. Stop the WeKan service
3. Update to WeKan version 8.21 or later
4. Restart the WeKan service
5. Verify the update was successful
🔧 Temporary Workarounds
Restrict network access
linuxLimit access to WeKan instance to trusted networks only
Use firewall rules to restrict access: iptables -A INPUT -p tcp --dport [wekan-port] -s [trusted-network] -j ACCEPT
iptables -A INPUT -p tcp --dport [wekan-port] -j DROP
🧯 If You Can't Patch
- Implement strict access controls and user permissions within WeKan
- Monitor attachment access logs for suspicious activity
🔍 How to Verify
Check if Vulnerable:
Check WeKan version in admin panel or via API endpointCheck Version:
curl -s http://[wekan-host]:[port]/api/version || check admin panelVerify Fix Applied:
Confirm version is 8.21 or higher and test attachment access controls📡 Detection & Monitoring
Log Indicators:
- Unusual attachment access patterns
- Failed access attempts to restricted attachments
- Multiple attachment operations from single user in short time
Network Indicators:
- Unusual API calls to attachment endpoints
- Traffic patterns suggesting attachment enumeration
SIEM Query:
source="wekan" AND (attachment_access OR file_download) AND user NOT IN [authorized_users]