CVE-2026-44456: Hono BodyLimit() Can Be Bypassed For Vulnerability

MODERATE
Advisory Identifier: GHSA-9vqf-7f2p-gf9v
Share
CVSS 6.5
CWE-400
Published
Advisory Summary

CVE-2026-44456 is a MODERATE (CVSS 6.5) bodylimit() can be bypassed for vulnerability (CWE-400: Uncontrolled Resource Consumption) affecting Hono libraries in the npm ecosystem. The issue involves bodylimit() can be bypassed for chunked / unknown-length requests. Remediation is available by upgrading affected packages to version 4.12.16.

CVE-2026-44456 at a Glance

CVE Identifier CVE-2026-44456
GHSA Identifier GHSA-9vqf-7f2p-gf9v
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-400: Uncontrolled Resource Consumption
Affected Product Hono
Package Ecosystem npm
Published Date
Last Updated

Security Impact

CVSS: 6.5

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N).

Attack Vector Network (AV:N)
Attack Complexity Low (AC:L)
Privileges Required None (PR:N)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability None (A:N)

How to Fix CVE-2026-44456

To remediate this vulnerability, upgrade all affected Hono dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

hono fixed: 4.12.16 
npm install hono@4.12.16
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

npm ls hono

How to Check if You Are Affected

To determine whether your Node.js application is affected by CVE-2026-44456, inspect your project dependencies using npm:

npm ls hono

Analyze the terminal output to locate any version of Hono in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 4.12.16), your application is affected.

Note: The npm ls hono command inspects dependencies declared in your package.json and lockfile; it does not perform automated runtime dynamic scanning.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-400: Uncontrolled Resource Consumption, where the product does not properly control the allocation and maintenance of a limited resource. In Hono, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

## Summary `bodyLimit()` does not reliably enforce `maxSize` for requests without a usable `Content-Length` (e.g. `Transfer-Encoding: chunked`). Oversized requests can reach handlers and return `200` instead of `413`. ## Details For chunked / unknown-length requests, `bodyLimit()` wraps the body in a stream that counts bytes asynchronously, then runs the handler before the size decision is final. The `413` is only applied afterwards by checking `c.error`. This lets the limit be bypassed when: - the handler does not read the body, - the handler reads only the first chunk(s) and returns, or - the handler reads the body but swallows the read error in `try/catch`. In all three cases the handler returns `200` before the limit check completes (or its result is observed). The fix is to enforce the size decision before `next()` runs, instead of retrofitting the response via `c.error` afterwards. ## Impact Applications relying on `bodyLimit()` as a hard boundary can be bypassed: oversized chunked requests can reach handler logic and return successful responses. Per-request data exposure is bounded by `maxSize`, but the documented guarantee — "oversized requests are rejected before business logic runs" — does not hold. ## Credits - @lalalala5678 (slow chunked / early return variants) - @Jvr2022 (error handling bypass)

CVE-2026-44456 Affected Hono Versions

1 component(s)
Fixed Versions:
4.12.16
Product / Package Ecosystem Affected Versions Fixed Version
hono
npm/hono
npm
< 4.12.16
4.12.16

References

GitHub Advisory / Wiki ADVISORY
https://github.com/honojs/hono/security/advisories/GHSA-9vqf-7f2p-gf9v
NVD — CVE-2026-44456 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-44456
Hono Source Repository REPOSITORY
https://github.com/honojs/hono

Frequently Asked Questions

What is CVE-2026-44456?
CVE-2026-44456 is a security vulnerability in Hono involving bodyLimit() can be bypassed for chunked / unknown-length requests under CWE-400: Uncontrolled Resource Consumption.
Which Hono versions are affected?
Affected versions include releases prior to 4.12.16 across affected packages: hono.
What version fixes CVE-2026-44456?
Upgrading to 4.12.16 (or the latest patched release for your respective branch) resolves the vulnerability.
Is hono affected?
Yes, hono is affected in releases prior to 4.12.16. Upgrade your dependency to 4.12.16 or later.
What is the CVSS score of CVE-2026-44456?
CVE-2026-44456 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N.
What CWE is associated with CVE-2026-44456?
CVE-2026-44456 is classified under CWE-400: Uncontrolled Resource Consumption (The product does not properly control the allocation and maintenance of a limited resource.).
How can I check npm dependencies for CVE-2026-44456?
Run the dependency tree command: 'npm ls hono'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-9vqf-7f2p-gf9v",
  "modified" : "2026-05-14T20:32:03Z",
  "published" : "2026-05-06T23:50:10Z",
  "aliases" : [ "CVE-2026-44456" ],
  "summary" : "Hono: bodyLimit() can be bypassed for chunked / unknown-length requests",
  "details" : "## Summary\n\n`bodyLimit()` does not reliably enforce `maxSize` for requests without a usable `Content-Length` (e.g. `Transfer-Encoding: chunked`). Oversized requests can reach handlers and return `200` instead of `413`.\n\n## Details\n\nFor chunked / unknown-length requests, `bodyLimit()` wraps the body in a stream that counts bytes asynchronously, then runs the handler before the size decision is final. The `413` is only applied afterwards by checking `c.error`.\n\nThis lets the limit be bypassed when:\n\n- the handler does not read the body,\n- the handler reads only the first chunk(s) and returns, or\n- the handler reads the body but swallows the read error in `try/catch`.\n\nIn all three cases the handler returns `200` before the limit check completes (or its result is observed).\n\nThe fix is to enforce the size decision before `next()` runs, instead of retrofitting the response via `c.error` afterwards.\n\n## Impact\n\nApplications relying on `bodyLimit()` as a hard boundary can be bypassed: oversized chunked requests can reach handler logic and return successful responses. Per-request data exposure is bounded by `maxSize`, but the documented guarantee — \"oversized requests are rejected before business logic runs\" — does not hold.\n\n## Credits\n\n- @lalalala5678 (slow chunked / early return variants)\n- @Jvr2022 (error handling bypass)",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "npm",
      "name" : "hono"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.12.16"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "WEB",
    "url" : "https://github.com/honojs/hono/security/advisories/GHSA-9vqf-7f2p-gf9v"
  }, {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-44456"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/honojs/hono"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-400" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-05-06T23:50:10Z",
    "nvd_published_at" : "2026-05-13T16:16:57Z"
  }
}