CVE-2026-54003

CRITICAL

Kirby: External Initialization of the Panel on reverse proxy setups with the `Forwarded` header

Title source: cna
STIX 2.1

Description

Kirby is an open-source content management system. Prior to 4.9.4 and from 5.4.4, Kirby sites with no configured user accounts that run on publicly accessible servers behind a reverse proxy setting the Forwarded, X-Client-IP, or X-Real-IP request header could allow remote attackers to install the Panel and create the first admin user because local-IP checks trusted those headers incorrectly. This issue is fixed in versions 4.9.4 and 5.4.4.

References (8)

Core 8
Core References
X_Refsource_Misc x_refsource_misc
https://github.com/getkirby/kirby/pull/8166
X_Refsource_Misc x_refsource_misc
https://github.com/getkirby/kirby/releases/tag/4.9.4
X_Refsource_Misc x_refsource_misc
https://github.com/getkirby/kirby/releases/tag/5.4.4

Scores

CVSS v4 9.1
EPSS 0.0054
EPSS Percentile 42.7%
CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

CISA SSVC

Vulnrichment
Exploitation none
Automatable yes
Technical Impact partial

Details

CWE
CWE-454
Status published
Products (2)
getkirby/kirby < 4.9.4
getkirby/kirby >= 5.0.0, < 5.4.4
Published Jul 09, 2026
Tracked Since Jul 10, 2026