GitHub Advisoryadvisory · npm

GHSA-92vj-g62v-jqhh Hono has Body Limit Middleware Bypass

MEDIUM Published 2025-09-12 Modified 2025-09-12 Official page ↗
Aliases
CVE-2025-59139
Ecosystem
npm
Packages
hono
Severity
Moderate
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Weaknesses
CWE-400, CWE-770
Reviewed
2025-09-12

Affected packages

• npm hono: < 4.9.7 → fixed in 4.9.7

Description

Summary A flaw in the `bodyLimit` middleware could allow bypassing the configured request body size limit when conflicting HTTP headers were present. Details The middleware previously prioritized the `Content-Length` header even when a `Transfer-Encoding: chunked` header was also included. According to the HTTP specification, `Content-Length` must be ignored in such cases. This discrepancy could allow oversized request bodies to bypass the configured limit. Most standards-compliant runtimes and reverse proxies may reject such malformed requests with `400 Bad Request`, so the practical impact depends on the runtime and deployment environment. Impact If body size limits are used as a safeguard against large or malicious requests, this flaw could allow attackers to send oversized request bodies. The primary risk is denial of service (DoS) due to excessive memory or CPU consumption when handling very large requests. Resolution The implementation has been updated to align with the HTTP specification, ensuring that `Transfer-Encoding` takes precedence over `Content-Length`. The issue is fixed in Hono v4.9.7, and all users should upgrade immediately.

Related

Alias · CVE (1)

  • CVE-2025-59139 Hono is a Web application framework that provides support for any JavaScript runtime. vulnerability

Weakness · CWE (2)

  • CWE-400 Uncontrolled Resource Consumption weakness
  • CWE-770 Allocation of Resources Without Limits or Throttling weakness

References