CVE-2025-40710

Host Header Injection (HHI) vulnerability in the Hotspot Shield VPN client, which can induce unexpected behaviour when accessing third-party web applications through the VPN tunnel. Although such applications do not present this vulnerability per se, the use of the tunnel, together with a forged Host header, can cause the VPN client to redirect or forward HTTP requests to servers other than those originally intended, leading to consequences such as open redirects or delivery of traffic to infrastructure controlled by an attacker. This does not imply a flaw in the target applications, but in how the VPN client internally handles outgoing headers and requests.

CVSS

No CVSS.

References

Link	Resource
https://www.incibe.es/en/incibe-cert/notices/aviso/host-header-injection-hhi-hotspot-shield-vpn-client

Configurations

No configuration.

History

15 Apr 2026, 00:35

Type	Values Removed	Values Added
Summary		(es) Vulnerabilidad de inyección de encabezado de host (HHI) en el cliente VPN de Hotspot Shield, que puede inducir un comportamiento inesperado al acceder a aplicaciones web de terceros a través del túnel VPN. Si bien estas aplicaciones no presentan esta vulnerabilidad en sí, el uso del túnel, junto con un encabezado de host falsificado, puede provocar que el cliente VPN redirija o reenvíe solicitudes HTTP a servidores distintos a los previstos originalmente, lo que puede tener consecuencias como redirecciones abiertas o la entrega de tráfico a la infraestructura controlada por un atacante. Esto no implica una falla en las aplicaciones objetivo, sino en la forma en que el cliente VPN gestiona internamente los encabezados y solicitudes salientes.

30 Jun 2025, 11:15

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-06-30 11:15

Updated : 2026-06-17 09:22

NVD link : CVE-2025-40710

Mitre link : CVE-2025-40710

CVE.ORG link : CVE-2025-40710

JSON object : View

Products Affected

No product.

CWE

CWE-74

Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')

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