Improper Authentication The advisory has been revoked - it doesn't affect any version of package kanboard (opens in a new tab)
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-DEBIAN14-KANBOARD-14906034
- published9 Jan 2026
- disclosed8 Jan 2026
Introduced: 8 Jan 2026
CVE-2026-21881 (opens in a new tab)Amendment
The Debian security team deemed this advisory irrelevant for Debian:14.
NVD Description
Note: Versions mentioned in the description apply only to the upstream kanboard package and not the kanboard package as distributed by Debian.
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.