CVE-2026-29087: @hono/node-server allows running the Hono application on Node.js. Prior to version 1.19.10, when using @hono/node-server's static file serving togethe...

Description

@hono/node-server allows running the Hono application on Node.js. Prior to version 1.19.10, when using @hono/node-server's static file serving together with route-based middleware protections (e.g. protecting /admin/*), inconsistent URL decoding can allow protected static resources to be accessed without authorization. In particular, paths containing encoded slashes (%2F) may be evaluated differently by routing/middleware matching versus static file path resolution, enabling a bypass where middleware does not run but the static file is still served. This issue has been patched in version 1.19.10.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS Probability

0.33%

24.4th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-863

Affected Software

Vendor	Product	Versions
Hono	Node-Server	< 1.19.10

References

Timeline

Published: Mar 6, 2026
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2026-29087?

@hono/node-server allows running the Hono application on Node.js. Prior to version 1.19.10, when using @hono/node-server's static file serving together with route-based middleware protections (e.g. protecting /admin/*), inconsistent URL decoding can allow protected static resources to be accessed without authorization. In particular, paths containing encoded slashes (%2F) may be evaluated differently by routing/middleware matching versus static file path resolution, enabling a bypass where middleware does not run but the static file is still served. This issue has been patched in version 1.19.10.

How severe is CVE-2026-29087?

CVE-2026-29087 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.33% probability of exploitation in the next 30 days.

How do I fix CVE-2026-29087?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.