CVE-2026-117477GMO Prime Strategy Co., Ltd. KUSANAGI 7 Security Edition HTTP response splitting
CVE-2026-117477 is a HTTP response splitting in GMO Prime Strategy Co., Ltd. KUSANAGI 7 Security Edition, rated medium (5.1 on CVSS 4.0).
Why this priority: Medium severity, with no exploitation signal.
Published · Updated · NVD status: Received
What it is
Line breaks in input let an attacker add headers or a second response.
How it is reached
An attacker can exploit it over the network, without an account, but someone has to act first, such as opening a file or following a link.
What an attacker gains
The scored direct impact on the component itself is low. In practice, this kind of flaw lets an attacker smuggle requests past the proxy's checks. The damage can spread past the vulnerable component into others.
Is it being exploited?
There is no public report of exploitation yet.
What to do
- No fixed version is listed yet. Find every place GMO Prime Strategy Co., Ltd. KUSANAGI 7 Security Edition runs, watch the references for a fix, and plan a replacement if it is no longer supported.
- While there is no fix, keep it off the internet or behind a VPN, allowlist or authenticating proxy.
- Warn the people who use it, and filter files and links on the way in.
Description from NVD
KUSANAGI provided by GMO Prime Strategy Co., Ltd. contains an HTTP header injection vulnerability that may allow arbitrary HTTP headers to be injected into the HTTP response when a user accesses a specially crafted URL.
What this means for your architecture.
A CVE names a product. Whether it matters depends on where that product sits in your systems: what reaches it, which trust boundary it guards and what it can reach once compromised. Veriom maps your components, their relationships and your trust boundaries from your code, cloud and delivery evidence, so you can see where a component like this sits. The radar itself does not look at your systems.
Components it touches
- Proxies, load balancers and the servers behind them. The flaw sits between a front-end proxy and its back end.
Trust boundaries in play
- Internet-facing entry points. No account is needed. Any instance reachable from outside your perimeter, through a load balancer, gateway, VPN or exposed admin port, is in scope.
- People who open files and links. Mail, chat and browsers are the delivery path.
- Isolation between components. The impact crosses out of the vulnerable component into others it should be isolated from.
- Between a front-end proxy and its back end. An attacker who crosses it can smuggle requests past the proxy's checks.
Questions to answer about your own systems
- Where does GMO Prime Strategy Co., Ltd. KUSANAGI 7 Security Edition run in your systems, and at which version?
- Which of those instances can be reached from the internet or partner networks?
- What can it reach once compromised: which data stores, secrets and services?
Sources
- CVE records and CVSS scores from the NVD CVE API. This product uses the NVD API but is not endorsed or certified by the NVD.
- Exploitation status from CISA’s Known Exploited Vulnerabilities catalog.
- Exploit likelihood from FIRST’s Exploit Prediction Scoring System (EPSS), refreshed daily.
- Explanations are written by Veriom from fixed templates over each record’s data, not by a person reviewing each CVE. Descriptions are quoted from the records as published.