{"id":"CVE-2026-21879","summary":"Kanboard vulnerable to Open Redirect via protocol-relative URLs","details":"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.","aliases":["GHSA-mhv9-7m9w-7hcq"],"modified":"2026-08-12T03:51:46.321210617Z","published":"2026-01-08T00:51:50.954Z","database_specific":{"cna_assigner":"GitHub_M","cwe_ids":["CWE-601"],"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21879.json"},"references":[{"type":"WEB","url":"https://github.com/kanboard/kanboard/releases/tag/v1.2.49"},{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21879.json"},{"type":"ADVISORY","url":"https://github.com/kanboard/kanboard/security/advisories/GHSA-mhv9-7m9w-7hcq"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-21879"},{"type":"FIX","url":"https://github.com/kanboard/kanboard/commit/93bcae03301a6d34185a8dba977417e6b3de519f"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/kanboard/kanboard","events":[{"introduced":"0"},{"fixed":"f0f7d27007f5a788f14416c548421efd740b7bce"},{"fixed":"93bcae03301a6d34185a8dba977417e6b3de519f"}],"database_specific":{"cpe":"cpe:2.3:a:kanboard:kanboard:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"fixed":"1.2.49"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["v1.2.47","v1.2.46","v1.2.45","v1.2.44","v1.2.43","v1.2.42","v1.2.41","v1.2.40","v1.2.39","v1.2.38","v1.2.37","v1.2.36","v1.2.35","v1.2.34","v1.2.33","v1.2.32","v1.2.31","v1.2.30","v1.2.29","v1.2.28","v1.2.27","v1.2.26","v1.2.25","v1.2.24","v1.2.23","v1.2.22","v1.2.21","v1.2.20","v1.2.19","v1.2.18","v1.2.17","v1.2.16","v1.2.15","v1.2.14","v1.2.13","v1.2.12","v1.2.11","v1.2.10","v1.2.9","v1.2.8","v1.2.7","v1.2.6","v1.2.5","v1.2.4","v1.2.3","v1.2.2","v1.2.1","v1.2.0","v1.1.1","v1.1.0","v1.0.48","v1.0.46","v1.0.45","v1.0.44","v1.0.43","v1.0.42","v1.0.41","v1.0.40","v1.0.39","v1.0.38","v1.0.37","v1.0.36","v1.0.35","v1.0.34","v1.0.33","v1.0.32","v1.0.31","v1.0.30","v1.0.29","v1.0.28","v1.0.27","v1.0.26","v1.0.20","v1.0.19","v1.0.18","v1.0.17","v1.0.16","v1.0.15","v1.0.14","v1.0.13","v1.0.12","v1.0.11","v1.0.10","v1.0.9","v1.0.8","v1.0.7","v1.0.6","v1.0.5","v1.0.4","v1.0.3","v1.0.2","v1.0.1","v1.0.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-21879.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:N/A:N"}]}