Vulnerability · Published Jun 30, 2025 · Assigned by INCIBE
CVE-2025-40710Host Header Injection (HHI) in the Hotspot Shield VPN client
Low 2.3
In plain English
A low-severity injection in Hotspot Shield VPN client from Hotspot Shield. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 25% of all known vulnerabilities).
Official description
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.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Hotspot Shield | Hotspot Shield VPN client | 12.9.2 |
Weakness: CWE-74 · Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:N/UI:P/VC:N/VI:N/VA:L/SC:N/SI:L/SA:N