CVE-2026-59895

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class...

CVE-2026-59896

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.11.8 before 4.12.27, hono/jsx did not isolate context values per request during server-side rendering, allowing createContext, useContext, jsxRenderer, or useRequestContext data from a different in-flight...

CVE-2026-59897

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.3.3 before 4.12.27, the AWS API Gateway v1 adapter can drop a distinct repeated request header value because it de-duplicates values using a substring comparison instead of an exact match, so middleware o...

EUVD-2026-42327

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class...

CVE-2026-59895

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class...

CVE-2026-59895

Hono (server-side JS framework) contains a CS/XSS flaw in cx() within hono/css: class name construction concatenates strings and marks the result as pre-escaped, bypassing HTML escaping. This allows untrusted className values used in a JSX class attribute during server-side rendering to break out...

CVE-2026-59895 Hono: Server-Side XSS via JSX Escaping Bypass in cx() Utility

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.0.0 before 4.12.27, cx in hono/css composes class names from plain strings but marks the result as already escaped without HTML-escaping the input, allowing untrusted className values used in a JSX class...

EUVD-2026-42326

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.11.8 before 4.12.27, hono/jsx did not isolate context values per request during server-side rendering, allowing createContext, useContext, jsxRenderer, or useRequestContext data from a different in-flight...

CVE-2026-59897 Hono: API Gateway v1 adapter can drop a distinct repeated request header value during de-duplication

Hono is a Web application framework that provides support for any JavaScript runtime. From 4.3.3 before 4.12.27, the AWS API Gateway v1 adapter can drop a distinct repeated request header value because it de-duplicates values using a substring comparison instead of an exact match, so middleware o...

CVE-2025-71381

Hono before 4.10.2 fixed in 4.10.3 contains a flaw in its CORS middleware: when the origin is not set to "", the middleware copies the Vary header from the incoming request into the response. Because Vary is a response header that should be managed by the server, an attacker can supply arbitrary...

CVE-2026-56761

CVE-2026-56761 affects the hono framework prior to 4.12.14, where server-side rendering of JSX allows HTML injection through malformed attribute names. Attackers can craft attribute keys containing characters like quotes or angle brackets, breaking tag boundaries and injecting unintended attribut...

CVE-2026-54288

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, the Body Limit Middleware trusts the request's Content-Length header to decide whether a body is within the limit. On AWS Lambda API Gateway v1/v2, ALB, VPC Lattice, and Lambda@Edge the body is...

CVE-2026-54287

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on AWS Lambda, the ALB single-header response and the VPC Lattice v2 response join multiple Set-Cookie headers into one comma-separated value. Because commas also appear inside cookie attribute...

CVE-2026-54290

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, with credentials: true and no explicit origin the default wildcard, the CORS Middleware reflects the request's Origin and sends Access-Control-Allow-Credentials: true. Any site can then make...

CVE-2026-54289

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on AWS Lambda@Edge, CloudFront delivers a request header that appears more than once as several separate entries. The adapter writes each value with Headers.set instead of Headers.append, so...

CVE-2026-54286

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on Windows hosts, an encoded backslash %5C in the request path decodes to , which the Windows path resolver treats as a separator. serve-static then resolves a single URL segment such as...

CVE-2026-54288 Hono: Body Limit Middleware can be bypassed on AWS Lambda by understating `Content-Length`

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, the Body Limit Middleware trusts the request's Content-Length header to decide whether a body is within the limit. On AWS Lambda API Gateway v1/v2, ALB, VPC Lattice, and Lambda@Edge the body is...

CVE-2026-54288

The CVE-2026-54288 issue affects the Hono Web framework prior to version 4.12.25, where the Body Limit Middleware trusts the request Content-Length header. On AWS Lambda environments (API Gateway v1/v2, ALB, VPC Lattice, and Lambda@Edge), the body is fully buffered and the adapter builds the requ...

CVE-2026-54289 Hono: Lambda@Edge adapter keeps only the last value of a repeated request header, dropping the rest

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.25, on AWS Lambda@Edge, CloudFront delivers a request header that appears more than once as several separate entries. The adapter writes each value with Headers.set instead of Headers.append, so...

CVE-2026-54289

CVE-2026-54289 — Hono Lambda@Edge header handling : On AWS Lambda@Edge, prior to 4.12.25, CloudFront may deliver repeated headers as multiple entries. The Hono Lambda@Edge adapter uses Headers.set for each value, overwriting the previous one, so only the last value reaches the application. Header...