HTTP Request Smuggling Affecting hono package, versions <4.13.5
Threat Intelligence
The probability is the direct output of the EPSS model, and conveys an overall sense of the threat of exploitation in the wild. The percentile measures the EPSS probability relative to all known EPSS scores. Note: This data is updated daily, relying on the latest available EPSS model version. Check out the EPSS documentation for more details.
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Test your applications- Snyk IDSNYK-JS-HONO-19499091
- published2 Sept 2026
- disclosed1 Sept 2026
- creditUnknown
Introduced: 1 Sep 2026
NewCVE-2026-84363 (opens in a new tab)How to fix?
Upgrade hono to version 4.13.5 or higher.
Overview
hono is an Ultrafast web framework for the Edges
Affected versions of this package are vulnerable to HTTP Request Smuggling in its query parsing helpers, which do not terminate at the URL fragment and parse a ? appearing after a # as the start of the query string. An attacker can smuggle parameters past upstream allow/deny lists and validation, poison cache entries with unobserved parameters, or achieve stored XSS in cached HTML, by placing query parameters after a # fragment so browsers, new URL(), and reverse proxies ignore them while the query helpers still read them. This requires a literal # in the request URL to reach the application, and deployments behind intermediaries that strip fragments or runtimes that normalize URLs, such as Cloudflare Workers, are unaffected.