Skip to content
OpenAdvisories
Medium · 6.5 CVE-2026-54288 EUVD-2026-38331GHSA-rv63-4mwf-qqc2

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

Published Jun 22, 2026 · Updated Jun 23, 2026 · Assigned by GitHub_M

Description

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 delivered fully buffered and the adapter builds the request with the client-declared Content-Length, which need not match the actual payload. A client can declare a tiny Content-Length while sending a much larger body, slipping past the limit. This vulnerability is fixed in 4.12.25.

Affected products

VendorProductAffectedFixed
honojs hono < 4.12.25 —

Affected packages

EcosystemPackageAffectedFixedRecord
npm hono < 4.12.25 4.12.25 GHSA-rv63-4mwf-qqc2

Advisories 1

References