CVE-2026-47676

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.21, app.mount() strips the mount prefix from the incoming request path using the raw URL pathname, while route matching is performed against the percent-decoded path. This inconsistency causes the prefix to be stripped at the wrong position when the path contains percent-encoded multi-byte characters, resulting in the mounted sub-application receiving an incorrect path. This vulnerability is fixed in 4.12.21.

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-2gcr-mfcq-wcc3	Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*

History

No history.

Information

Published : 2026-05-28 17:16

Updated : 2026-06-17 10:54

NVD link : CVE-2026-47676

Mitre link : CVE-2026-47676

CVE.ORG link : CVE-2026-47676

JSON object : View

Products Affected

hono

hono

CWE

CWE-444

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

CWE-693

Protection Mechanism Failure

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