CVE-2026-107303 JHipster: Generated Applications Allow Stored XSS via Unrestricted Blob ContentType Opened as Same-Origin Blob
Attackers can inject malicious scripts into JHipster-generated apps via stored blobs, leading to code execution when viewed by other users.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-107303?
CVE-2026-107303 is a high-severity cross-site scripting vulnerability in generator-jhipster, published on 8 Oct 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Official description
JHipster is a development platform to quickly generate, develop, and deploy modern web applications and microservice architectures. Prior to generator-jhipster 9.4.0 and react-jhipster 1.1.0, generated applications can persist attacker-controlled Blob data and companion ContentType values, return them through generated REST endpoints, and pass them to the generated openFile helper in generators/client/generators/common/templates/src/main/webapp/app/shared/jhipster/data-utils.ts.ejs. The helper uses the returned ContentType as the browser Blob MIME type and opens an object URL, so a normal authenticated user with write access to a Blob-bearing entity can store active HTML or SVG content that may execute under the application origin when a privileged user opens it. Exploitability depends on the generated application's content security policy and target-browser Blob behavior. This issue is fixed in generator-jhipster 9.4.0 and react-jhipster 1.1.0.
Weakness: CWE-79
Which versions are affected by CVE-2026-107303?
4 open source packages ship an affected version, including generator-jhipster and react-jhipster.
| Package | Affected | Fixed in |
|---|---|---|
generator-jhipster npm | All versions | 9.4.0 |
generator-jhipster npm | All versions | 9.4.0 |
react-jhipster npm | All versions | 1.1.0 |
react-jhipster npm | All versions | 1.1.0 |
How do I fix CVE-2026-107303?
Upgrade generator-jhipster to 9.4.0 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2026-107303 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-107303 exists.
Sources
Also known as GHSA-9ffp-22j7-56r2.