CVE-2026-53446 in Wekan
Summary
by MITRE • 07/16/2026
Wekan is open source kanban built with Meteor. Prior to 9.32, Wekan webhook integration URLs in models/integrations.js are stored from user input and later fetched by server/notifications/outgoing.js without applying the existing validateAttachmentUrl() private-network checks from models/lib/attachmentUrlValidation.js. A board administrator can configure webhook URLs that cause server-side requests to internal or metadata services. This issue is fixed in version 9.32.
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 07/16/2026
The vulnerability described represents a critical server-side request forgery (SSRF) flaw in Wekan versions prior to 9.32, where the application fails to properly validate webhook URLs provided by users. This security weakness stems from the improper handling of user-supplied input within the models/integrations.js file, which stores webhook integration URLs directly from user configuration without adequate sanitization or validation mechanisms. The flaw occurs because the system lacks proper checks before executing outbound requests through server/notifications/outgoing.js, creating a pathway for malicious actors to manipulate the application's behavior.
The technical implementation of this vulnerability allows board administrators to configure webhook URLs that can trigger server-side requests to internal network services or metadata endpoints that should normally be restricted from external access. This represents a significant bypass of network security controls since the validation function validateAttachmentUrl() which exists in models/lib/attachmentUrlValidation.js and is designed to prevent private network access is not applied to webhook URL handling. The absence of this validation creates an attack surface where malicious users can potentially access internal systems, metadata services, or other restricted resources that would normally be protected by network segmentation.
The operational impact of this vulnerability extends beyond simple data exfiltration, as it enables attackers to perform reconnaissance activities against internal networks, potentially leading to further privilege escalation or lateral movement within the organization's infrastructure. The flaw particularly affects environments where Wekan is deployed in corporate or organizational settings with strict network security policies, as it can undermine the security boundaries between internal and external systems. This vulnerability aligns with CWE-918 which defines Server-Side Request Forgery as a weakness where an application receives a request from an untrusted source and uses that request to make a request to an internal system without proper validation.
The risk assessment for this vulnerability increases when considering the potential for automated exploitation, where attackers could configure webhooks pointing to malicious services that then attempt to access internal metadata endpoints or other sensitive systems. This type of attack vector is particularly concerning because it leverages legitimate application functionality to bypass security controls, making detection more difficult. The mitigation strategy involves implementing proper URL validation mechanisms that enforce the same checks used for attachment URLs, ensuring that webhook configurations cannot reference internal network resources without explicit authorization. Organizations should also consider implementing network segmentation and firewall rules to limit outbound connections from Wekan servers to prevent unauthorized access to internal systems.
This vulnerability demonstrates the importance of consistent security controls across all application components, particularly when handling user input that can influence server behavior. The fix implemented in version 9.32 addresses this by ensuring that webhook URL validation follows the same security patterns as other attachment-related functionality, thereby preventing unauthorized access to private network resources. Security practitioners should evaluate their Wekan deployments to ensure compliance with the patched version and implement additional monitoring to detect suspicious webhook configurations that might indicate attempted exploitation of similar vulnerabilities in other applications. The incident highlights the need for comprehensive input validation across all user-modifiable parameters within web applications, particularly those that influence network connectivity or system behavior.
The vulnerability can be classified under ATT&CK technique T1071.004 for Application Layer Protocol: DNS and T1046 for Network Service Scanning, as it enables attackers to probe internal services through the application's webhook functionality. Organizations should implement network-based detection measures such as intrusion detection systems that monitor for unusual outbound requests from Wekan servers, particularly those targeting private IP ranges or common metadata service endpoints like AWS metadata services or Azure instance metadata. The remediation process requires not only upgrading to version 9.32 but also conducting thorough security reviews of all user-modifiable configuration parameters within the application to ensure consistent validation and sanitization practices are applied throughout the codebase.