CVE-2026-21879: Kanboard

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

Kanboard is project management software focused on Kanban methodology. Versions 1.2.48 and below are vulnerable to an Open Redirect attack that allows malicious actors to redirect authenticated users to attacker-controlled websites. By crafting URLs such as //evil.com, attackers can bypass the filter_var($url, FILTER_VALIDATE_URL) validation check. This vulnerability could be exploited to conduct phishing attacks, steal user credentials, or distribute malware. The issue is fixed in version 1.2.49.

Affected products

• Kanboard Kanboard: before 1.2.49 (fixed in 1.2.49)

Published 2026-01-08. Last modified 2026-06-17.