CVE-2026-69207 Hono: ReDoS in CORS middleware via Access-Control-Request-Headers

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.34, the built-in CORS middleware, hono/cors, is vulnerable to a regular expression denial of service ReDoS. During a preflight OPTIONS request, the middleware parses the attacker-controlled...

CVE-2026-69207

Hono’s built-in CORS middleware (hono/cors) is vulnerable to a ReDoS in the Access-Control-Request-Headers parsing during preflight requests when allowHeaders is unset/empty. The regex-based parser can backtrack quadratically with long whitespace, potentially causing seconds of CPU usage per pref...

CVE-2026-71849

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.7.0 to 4.12.33, the Proxy Helper proxy function in hono/proxy does not remove response headers named by the origin's Connection header. Per RFC 9110 Section 7.6.1, an intermediary must remove the header...

CVE-2026-71850

Hono is a Web application framework that provides support for any JavaScript runtime. From 3.8.0 to 4.12.33, memo from hono/jsx retains the result of a server side render and reuses it for later renders with comparator equal props, and request scoped values read inside the component take no part ...

CVE-2026-71848

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.0 to 4.12.33, the languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen separated subtags. To...

CVE-2026-71850 Hono: `memo()` retains SSR output across requests, leading to cross-user data disclosure

Hono is a Web application framework that provides support for any JavaScript runtime. From 3.8.0 to 4.12.33, memo from hono/jsx retains the result of a server side render and reuses it for later renders with comparator equal props, and request scoped values read inside the component take no part ...

CVE-2026-71850

Hono is a Web application framework that provides support for any JavaScript runtime. From 3.8.0 to 4.12.33, memo from hono/jsx retains the result of a server side render and reuses it for later renders with comparator equal props, and request scoped values read inside the component take no part ...

CVE-2026-71850 Hono: `memo()` retains SSR output across requests, leading to cross-user data disclosure

Hono is a Web application framework that provides support for any JavaScript runtime. From 3.8.0 to 4.12.33, memo from hono/jsx retains the result of a server side render and reuses it for later renders with comparator equal props, and request scoped values read inside the component take no part ...

CVE-2026-71850 Hono: `memo()` retains SSR output across requests, leading to cross-user data disclosure

Hono is a Web application framework that provides support for any JavaScript runtime. From 3.8.0 to 4.12.33, memo from hono/jsx retains the result of a server side render and reuses it for later renders with comparator equal props, and request scoped values read inside the component take no part ...

CVE-2026-71849 Hono: Proxy Helper does not remove response headers listed in the `Connection` header

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.7.0 to 4.12.33, the Proxy Helper proxy function in hono/proxy does not remove response headers named by the origin's Connection header. Per RFC 9110 Section 7.6.1, an intermediary must remove the header...

CVE-2026-71849 Hono: Proxy Helper does not remove response headers listed in the `Connection` header

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.7.0 to 4.12.33, the Proxy Helper proxy function in hono/proxy does not remove response headers named by the origin's Connection header. Per RFC 9110 Section 7.6.1, an intermediary must remove the header...

CVE-2026-71848

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.0 to 4.12.33, the languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen separated subtags. To...

CVE-2026-71848 Hono: Algorithmic Complexity DoS in Language Middleware

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.0 to 4.12.33, the languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen separated subtags. To...

CVE-2026-71848 Hono: Algorithmic Complexity DoS in Language Middleware

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.12.0 to 4.12.33, the languageDetector middleware is vulnerable to algorithmic complexity denial of service when processing a crafted language tag containing a large number of hyphen separated subtags. To...

CVE-2026-71848

Summary: CVE-2026-71848 affects the Hono web framework (4.12.0–4.12.33) via the languageDetector middleware. The root cause is an implementation in normalizeLanguage() that builds language tag prefixes with parts.slice(0, i).join('-') for every possible prefix, causing the total string processing...

Regular Expression Denial of Service (ReDoS)

Overview hono is an Ultrafast web framework for the Edges Affected versions of this package are vulnerable to Regular Expression Denial of Service ReDoS in the cors middleware during the parsing of the Access-Control-Request-Headers header via a regular expression with quadratic runtime complexit...

CVE-2026-59895

A flaw was found in Hono, a web application framework. The cx function within hono/css improperly handles class names during server-side rendering. This allows an attacker to inject untrusted values into a JSX class attribute, leading to the injection of arbitrary markup. This could result in...

CVE-2026-59897

A flaw was found in Hono, a web application framework. The AWS API Gateway v1 adapter incorrectly de-duplicates repeated request header values using a substring comparison, rather than an exact match. This can lead to incomplete data being received by middleware or application logic that relies o...

CVE-2026-59896

A flaw was found in Hono, a Web application framework. The hono/jsx component did not properly isolate context values per request during server-side rendering. This allowed data from a different in-flight request to be used after an asynchronous operation in a component. This could lead to...

Node.js Adapter for Hono: Unauthenticated memory-leak DoS via aborted WebSocket handshake

Summary A WebSocket upgrade request to an upgradeWebSocket route with a missing or malformed Sec-WebSocket-Key header leaks memory permanently. The request's IncomingMessage is retained in an internal map and a pending promise is never settled, even though no connection is established. Since the...