Vulnerability in Honojs Hono
CVE-2026-109955
Hono from 4.12.4 before 4.13.11 contains a middleware bypass vulnerability in serveStatic that allows unauthenticated attackers to skip prefix middleware by exploiting double path decoding. Attackers can send malformed percent-encoded paths that the router matches in encoded form, reaching static files without authentication checks running.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:N/A:N.
EPSS exploit prediction
No EPSS score from FIRST.org yet. New CVEs usually get one within a few days; no score means no signal yet, not low risk. How EPSS works.
Affected products
Weakness classification (CWE)
References
- github.com/honojs/hono/security/advisories/GHSA-5r4p-p66f-jhc7 (vendor-advisory)
- www.vulncheck.com/advisories/hono-4.12.4-before-4.13.11-middleware-bypass-via-s… (third-party-advisory)
Frequently asked questions
- What is CVE-2026-109955?
- CVE-2026-109955 is a medium-severity vulnerability in Honojs Hono, classified under CWE-174. CVSS score: 5.3/10. Published 2026-10-13.
- How severe is CVE-2026-109955?
- Medium severity. CVSS v3 base score is 5.3 out of 10.