CVE-2026-27116: Vikunja has Reflected HTML Injection via filter Parameter in Projects Module

Severity: medium (CVSS 6.1 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: yes
Published: 2026-02-25 · updated 2026-06-17
Weakness: CWE-79

Description

Vikunja is an open-source self-hosted task management platform. Prior to version 2.0.0, a reflected HTML injection vulnerability exists in the Projects module where the `filter` URL parameter is rendered into the DOM without output encoding when the user clicks "Filter." While `<script>` and `<iframe>` are blocked, `<svg>`, `<a>`, and formatting tags (`<h1>`, `<b>`, `<u>`) render without restriction — enabling SVG-based phishing buttons, external redirect links, and content spoofing within the trusted application origin. Version 2.0.0 fixes this issue.

Affected products

go-vikunja vikunja: before 2.0.0 — fixed in 2.0.0

How to fix

Upgrade to a fixed version: go-vikunja vikunja 2.0.0. Check the vendor advisory for mitigations.

References

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