CVE-2026-33335

Vikunja is an open-source self-hosted task management platform. Starting in version 0.21.0 and prior to version 2.2.0, the Vikunja Desktop Electron wrapper passes URLs from `window.open()` calls directly to `shell.openExternal()` without any validation or protocol allowlisting. An attacker who can place a link with `target="_blank"` (or that otherwise triggers `window.open`) in user-generated content can cause the victim's operating system to open arbitrary URI schemes, invoking local applications, opening local files, or triggering custom protocol handlers. Version 2.2.0 patches the issue.

CVSS v3 8.0 HIGH

8.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.1 / Impact : 5.9

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-6q44-85gc-cjvf	Exploit Vendor Advisory
https://vikunja.io/changelog/vikunja-v2.2.0-was-released	Release Notes
https://github.com/go-vikunja/vikunja/security/advisories/GHSA-6q44-85gc-cjvf	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:vikunja:vikunja:*:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-24 16:16

Updated : 2026-03-27 16:58

NVD link : CVE-2026-33335

Mitre link : CVE-2026-33335

CVE.ORG link : CVE-2026-33335

JSON object : View

Products Affected

vikunja

vikunja

CWE

CWE-939

Improper Authorization in Handler for Custom URL Scheme

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