CVE-2026-61503

Rejetto HFS 3.0.0 through 3.2.0 returns observably different responses from its login endpoint depending on whether the submitted username exists. A remote unauthenticated attacker can use this to confirm valid account names, including the default admin account, facilitating password-guessing and session-forgery attacks.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/rejetto/hfs/releases/tag/v3.2.1
https://www.vulncheck.com/advisories/rejetto-hfs-username-enumeration-via-login-response-differences

Configurations

No configuration.

History

24 Oct 2026, 22:10

Type	Values Removed	Values Added
Summary		(es) Rejetto HFS 3.0.0 hasta 3.2.0 devuelve respuestas observablemente diferentes desde su endpoint de inicio de sesión dependiendo de si el nombre de usuario enviado existe. Un atacante remoto no autenticado puede usar esto para confirmar nombres de cuenta válidos, incluyendo la cuenta de administrador predeterminada, facilitando ataques de adivinación de contraseñas y de falsificación de sesión.

Information

Published : 2026-07-13 18:16

Updated : 2026-10-24 22:10

NVD link : CVE-2026-61503

Mitre link : CVE-2026-61503

CVE.ORG link : CVE-2026-61503

JSON object : View

Products Affected

No product.

CWE

CWE-204

Observable Response Discrepancy

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