Open Redirect in Kanboard
CVE-2026-21879
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.
Vulnerability class: Open Redirect
Published · last modified .
CVSS v3 metric
CVSS v3 base score 4.7 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N.
EPSS exploit prediction
EPSS: 0.003 (20.9th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 21st percentile — 20.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: +0.000
Affected products
- Kanboard — versions < 1.2.49
Weakness classification (CWE)
References
- github.com/kanboard/kanboard/security/advisories/GHSA-mhv9-7m9w-7hcq (Exploit, Third Party Advisory)
- github.com/kanboard/kanboard/commit/93bcae03301a6d34185a8dba977417e6b3de519f (Patch)
- github.com/kanboard/kanboard/releases/tag/v1.2.49 (Release Notes)
Frequently asked questions
- What is CVE-2026-21879?
- CVE-2026-21879 is a medium-severity vulnerability in Kanboard, classified under URL Redirection to Untrusted Site (Open Redirect). CVSS score: 4.7/10. Published 2026-01-08.
- How severe is CVE-2026-21879?
- Medium severity. CVSS v3 base score is 4.7 out of 10.