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.

CVSS v3 5.3 MEDIUM

5.3^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 3.9 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/honojs/hono/security/advisories/GHSA-5r4p-p66f-jhc7
https://www.vulncheck.com/advisories/hono-4.12.4-before-4.13.11-middleware-bypass-via-servestatic-double-decoding

Configurations

No configuration.

History

13 Oct 2026, 14:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-13 14:17

Updated : 2026-10-13 14:17

NVD link : CVE-2026-109955

Mitre link : CVE-2026-109955

CVE.ORG link : CVE-2026-109955

JSON object : View

Products Affected

No product.

CWE

CWE-174

Double Decoding of the Same Data

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