{"id":"CVE-2026-54288","aliases":["GHSA-rv63-4mwf-qqc2"],"url":"https://o3.security/vulnerability/CVE-2026-54288","summary":"Hono: Body Limit Middleware can be bypassed on AWS Lambda by understating `Content-Length`","details":"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.","published":"2026-06-22T17:18:24.532Z","modified":"2026-08-12T03:51:44.402947288Z","cvss":{"score":6.5,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N"},"epss":{"score":0.00147,"percentile":0.04443,"asOf":"2026-08-23"},"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"npm","name":"hono","fixedVersion":"4.12.25"}],"fix":null,"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/54xxx/CVE-2026-54288.json"},{"type":"ADVISORY","url":"https://github.com/honojs/hono/security/advisories/GHSA-rv63-4mwf-qqc2"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-54288"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-08-12T03:51:44.402947288Z"}}