CVE-2026-54290 Hono: CORS Middleware reflects any Origin with credentials when `origin` defaults to the wildcard
The Hono CORS middleware incorrectly reflects any origin with credentials enabled, allowing attackers to read sensitive data from cookie-authenticated endpoints.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2026-54290?
CVE-2026-54290 is a high-severity vulnerability in honojs hono, published on 22 Jun 2026. An attacker can exploit it over the internet without logging in, and only if a user opens a file or follows a link.
Official description
Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, with credentials: true and no explicit origin (the default wildcard), the CORS Middleware reflects the request's Origin and sends Access-Control-Allow-Credentials: true. Any site can then make credentialed cross-origin requests and read the responses, exposing cookie-authenticated endpoints to arbitrary origins. This vulnerability is fixed in 4.12.25.
Weakness: CWE-942
Which versions are affected by CVE-2026-54290?
2 open source packages ship an affected version, including hono.
| Package | Affected | Fixed in |
|---|---|---|
hono npm | All versions | 4.12.25 |
hono npm | All versions | 4.12.25 |
How do I fix CVE-2026-54290?
Upgrade hono to 4.12.25 or later.
Is CVE-2026-54290 being exploited?
There is no known exploitation of CVE-2026-54290 in the wild and no public exploit code.
Sources
Also known as ECHO-dd9a-5b55-e04b, GHSA-88fw-hqm2-52qc, MINI-26jm-m79r-mw4j, MINI-4cjp-p875-3fm6, MINI-5273-prf6-h7f2, MINI-59vq-vf5w-3rhx and 10 more.