CVE-2026-21881

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Source
https://cve.org/CVERecord?id=CVE-2026-21881
Import Source
https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-21881.json
JSON Data
https://api.osv.dev/v1/vulns/CVE-2026-21881
Aliases
  • GHSA-wwpf-3j4p-739w
Downstream
Published
2026-01-08T01:08:01.853Z
Modified
2026-01-22T05:45:34.975008Z
Severity
  • 9.1 (Critical) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N CVSS Calculator
Summary
Kanboard is Vulnerable to Reverse Proxy Authentication Bypass
Details

Kanboard is project management software focused on Kanban methodology. Versions 1.2.48 and below is vulnerable to a critical authentication bypass when REVERSEPROXYAUTH 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.

Database specific 
{
    "cna_assigner": "GitHub_M",
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/21xxx/CVE-2026-21881.json",
    "cwe_ids": [
        "CWE-287"
    ]
}
References

Affected packages

Git / github.com/kanboard/kanboard

Affected ranges

Type
GIT
Repo
https://github.com/kanboard/kanboard
Events
Introduced
0 Unknown introduced commit / All previous commits are affected
Fixed
f0f7d27007f5a788f14416c548421efd740b7bce

Affected versions

v1.*
v1.0.0
v1.0.1
v1.0.10
v1.0.11
v1.0.12
v1.0.13
v1.0.14
v1.0.15
v1.0.16
v1.0.17
v1.0.18
v1.0.19
v1.0.2
v1.0.20
v1.0.21
v1.0.22
v1.0.23
v1.0.24
v1.0.25
v1.0.26
v1.0.27
v1.0.28
v1.0.29
v1.0.3
v1.0.30
v1.0.31
v1.0.32
v1.0.33
v1.0.34
v1.0.35
v1.0.36
v1.0.37
v1.0.38
v1.0.39
v1.0.4
v1.0.40
v1.0.41
v1.0.42
v1.0.43
v1.0.44
v1.0.45
v1.0.46
v1.0.47
v1.0.48
v1.0.5
v1.0.6
v1.0.7
v1.0.8
v1.0.9
v1.1.0
v1.1.1
v1.2.0
v1.2.1
v1.2.10
v1.2.11
v1.2.12
v1.2.13
v1.2.14
v1.2.15
v1.2.16
v1.2.17
v1.2.18
v1.2.19
v1.2.2
v1.2.20
v1.2.21
v1.2.22
v1.2.23
v1.2.24
v1.2.25
v1.2.26
v1.2.27
v1.2.28
v1.2.29
v1.2.3
v1.2.30
v1.2.31
v1.2.32
v1.2.33
v1.2.34
v1.2.35
v1.2.36
v1.2.37
v1.2.38
v1.2.39
v1.2.4
v1.2.40
v1.2.41
v1.2.42
v1.2.43
v1.2.44
v1.2.45
v1.2.46
v1.2.47
v1.2.5
v1.2.6
v1.2.7
v1.2.8
v1.2.9

Database specific

source 
"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-21881.json"