CVE-2025-40710 — Host Header Injection (HHI) in the Hotspot Shield VPN client
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 tun…
Published: 2025-06-30 · CVSS: 2.3 · CVSS 4.0
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.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7