CVE-2026-84363

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.13.5, Hono's query helpers treat a question mark after a literal hash fragment as the start of a query string, so the application can read request parameters that browsers, new URL(), reverse proxies, filtering rules, parameter allow and deny lists, access logging, request validation, and other middleware do not observe. The Cache Middleware removes the fragment when building its cache key, allowing a response influenced by parameters inside the fragment to be stored under a key that omits those parameters and later served to other users. This can bypass filtering and auditing, poison cached responses, and enable stored cross-site scripting when an affected parameter is reflected into cached HTML without escaping. Exploitation requires a runtime and intermediary path that passes a literal hash character through to the request URL; Cloudflare Workers and intermediaries that strip fragments are not affected. This issue is fixed in version 4.13.5.

CVSS v3 5.9 MEDIUM

5.9^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact HIGH

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/honojs/hono/commit/9c28d724c5a7fb086ebaa812fdc1ad6e957c63bc
https://github.com/honojs/hono/releases/tag/v4.13.5
https://github.com/honojs/hono/security/advisories/GHSA-crvj-82cr-hjcx

Configurations

No configuration.

History

No history.

Information

Published : 2026-09-01 21:18

Updated : 2026-09-09 21:09

NVD link : CVE-2026-84363

Mitre link : CVE-2026-84363

CVE.ORG link : CVE-2026-84363

JSON object : View

Products Affected

No product.

CWE

CWE-444

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

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