CVE-2026-63771

Adminer before 5.4.3 contains a cookie injection vulnerability that allows attackers to manipulate cookie attributes by injecting arbitrary values through the unsanitized X-Forwarded-Prefix HTTP header used in Set-Cookie path attributes. Attackers can exploit a misconfigured reverse proxy to downgrade SameSite protection and enable cross-origin authenticated requests, bypassing cookie security controls.

CVSS v3 7.1 HIGH

7.1^/10

CVSS v3 : HIGH

Vector :

Exploitability : 2.8 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact HIGH

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/vrana/adminer/issues/1298
https://github.com/vrana/adminer/releases#release-v5.4.3
https://github.com/vrana/adminer/security/advisories/GHSA-c533-9qwm-8w5h
https://www.vulncheck.com/advisories/adminer-cookie-injection-via-x-forwarded-prefix-header

Configurations

No configuration.

History

24 Oct 2026, 20:10

Type	Values Removed	Values Added
Summary		(es) Adminer anterior a la versión 5.4.3 contiene una vulnerabilidad de inyección de cookies que permite a los atacantes manipular atributos de cookies inyectando valores arbitrarios a través del encabezado HTTP X-Forwarded-Prefix sin sanear, utilizado en los atributos de ruta de Set-Cookie. Los atacantes pueden explotar un proxy inverso mal configurado para degradar la protección SameSite y habilitar solicitudes autenticadas de origen cruzado, eludiendo los controles de seguridad de las cookies.

Information

Published : 2026-07-20 19:17

Updated : 2026-10-24 20:10

NVD link : CVE-2026-63771

Mitre link : CVE-2026-63771

CVE.ORG link : CVE-2026-63771

JSON object : View

Products Affected

No product.

CWE

CWE-113

Improper Neutralization of CRLF Sequences in HTTP Headers ('HTTP Request/Response Splitting')

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