SB2026010728 - Multiple vulnerabilities in Kanboard
Published: January 7, 2026 Updated: January 9, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 3 vulnerabilities.
1) Open redirect (CVE-ID: CVE-2026-21879)
CWE-ID: CWE-601 - URL Redirection to Untrusted Site ('Open Redirect')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:N/SC:L/SI:N/SA:N/E:P/U:Clear
The vulnerability allows a remote attacker to redirect victims to arbitrary URL.
The vulnerability exists due to improper sanitization of user-supplied data within protocol-relative URLs. A remote attacker can create a link that leads to a trusted website, however, when clicked, redirects the victim to arbitrary domain.
Successful exploitation of this vulnerability may allow a remote attacker to perform a phishing attack and steal potentially sensitive information.
2) Improper Authentication (CVE-ID: CVE-2026-21881)
CWE-ID: CWE-287 - Improper Authentication
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:P/U:Amber
The vulnerability allows a remote attacker to bypass authentication process.
The vulnerability exists due to an error when REVERSE_PROXY_AUTH is enabled. A remote attacker can bypass authentication process and gain unauthorized access to the application.
3) LDAP injection (CVE-ID: CVE-2026-21880)
CWE-ID: CWE-90 - Improper Neutralization of Special Elements used in an LDAP Query ('LDAP Injection')
CVSSv4: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:P/U:Green
The vulnerability allows a remote attacker to bypass authentication process.
The vulnerability exists due to improper input validation within LDAP authentication mechanism. A remote attacker can send a specially crafted LDAP query to the application, bypass authentication process and gain unauthorized access to sensitive information on the system.
Remediation
Install update from vendor's website.