CVE-2026-54290: Hono permissive CORS policy in CORS Middleware

CVE-2026-54290 · Severity: high · CVSS 7.1 · Published 2026-06-22

Hono is a web application framework used to build JavaScript-based websites and services. A security flaw in its cross-origin resource sharing (CORS) settings allows malicious websites to bypass security protections and access sensitive data from a user's session. If a user visits a malicious site while logged into a Hono-based application, the attacker could read private information or perform actions on the user's behalf using their existing login cookies.

Technologies: hono (npm). Vendors: npm.

Quick answers

Is CVE-2026-54290 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-54290 being exploited in the wild.
How severe is CVE-2026-54290?
High severity, with a CVSS score of 7.1, published 22 June 2026.
Which products and versions are affected?
hono (npm) < 4.12.25, SEMVER:introduced=0,fixed=4.12.25.
Is there a fix for CVE-2026-54290?
Yes. hono (npm): upgrade to 4.12.25 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-54290 attacked?
It is attacked over the network, in a software library.
Am I affected by CVE-2026-54290?
Check whether you run hono (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

How to fix

  • hono (npm): upgrade to 4.12.25 or later
    npm install hono@4.12.25

Technical details

A vulnerability exists in Hono's CORS middleware when 'credentials: true' is enabled without a specific 'origin' defined. In this configuration, the middleware incorrectly reflects the 'Origin' header from the incoming request and responds with 'Access-Control-Allow-Credentials: true'. This behavior bypasses the browser's standard security restriction that prevents the use of wildcards with credentialed requests. An attacker can exploit this by hosting a malicious page that makes cross-origin requests to the vulnerable application; if a victim is authenticated via cookies, the attacker's script can read the response data. The issue is resolved in version 4.12.25 by ensuring the middleware does not reflect arbitrary origins when credentials are required.

Affected products

  • honojs Hono < 4.12.25

Identifiers

  • CVE-2026-54290
  • GHSA-88fw-hqm2-52qc

Timeline

  • 2026-06-09: advisory: GitHub Security Advisory published by maintainers
  • 2026-06-22: disclosed: CVE published to NVD
  • 2026-06-22: patched: Fix released in version 4.12.25

References

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