Auth bypass in Hono Node-Server
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.
Vulnerability class: Broken Access Control
EPSS: 0.003 (25.1th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.
Affected products
- Hono Node-server
- Honojs Node-server — versions < 1.19.10
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2026-29087?
- CVE-2026-29087 is a high-severity vulnerability in Hono Node-Server, classified under Incorrect Authorization. CVSS score: 7.5/10. Published 2026-03-06.
- How severe is CVE-2026-29087?
- High severity. CVSS v3 base score is 7.5 out of 10.