Kanboard is project management software focused on Kanban methodology. Versions 1.2.48 and below is vulnerable to a critical authentication bypass when REVERSE_PROXY_AUTH is enabled. The application blindly trusts HTTP headers for user authentication without verifying the request originated from a trusted reverse proxy. An attacker can impersonate any user, including administrators, by simply sending a spoofed HTTP header. This issue is fixed in version 1.2.49.
History

Thu, 08 Jan 2026 18:15:00 +0000

Type Values Removed Values Added
Metrics ssvc

{'options': {'Automatable': 'yes', 'Exploitation': 'poc', 'Technical Impact': 'total'}, 'version': '2.0.3'}


Thu, 08 Jan 2026 10:00:00 +0000

Type Values Removed Values Added
First Time appeared Kanboard
Kanboard kanboard
Vendors & Products Kanboard
Kanboard kanboard

Thu, 08 Jan 2026 01:30:00 +0000

Type Values Removed Values Added
Description Kanboard is project management software focused on Kanban methodology. Versions 1.2.48 and below is vulnerable to a critical authentication bypass when REVERSE_PROXY_AUTH is enabled. The application blindly trusts HTTP headers for user authentication without verifying the request originated from a trusted reverse proxy. An attacker can impersonate any user, including administrators, by simply sending a spoofed HTTP header. This issue is fixed in version 1.2.49.
Title Kanboard is Vulnerable to Reverse Proxy Authentication Bypass
Weaknesses CWE-287
References
Metrics cvssV3_1

{'score': 9.1, 'vector': 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N'}


cve-icon MITRE

Status: PUBLISHED

Assigner: GitHub_M

Published:

Updated: 2026-01-08T17:13:05.216Z

Reserved: 2026-01-05T17:24:36.928Z

Link: CVE-2026-21881

cve-icon Vulnrichment

Updated: 2026-01-08T17:12:55.062Z

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-01-08T02:15:53.803

Modified: 2026-01-08T18:15:59.500

Link: CVE-2026-21881

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-01-08T09:47:39Z