Hono allows bypass of CSRF Middleware by a request without Content-Type header.

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

5.9 · CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:L/I:H/A:N

EPSS

• CVE-2024-48913: 0.33% estimated exploitation activity in the next 30 days; percentile 25.64 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Summary Bypass CSRF Middleware by a request without Content-Type herader. Details Although the csrf middleware verifies the Content-Type Header, Hono always considers a request without a Content-Type header to be safe. https://github.com/honojs/hono/blob/cebf4e87f3984a6a034e60a43f542b4c5225b668/src/middleware/csrf/index.ts#L76-L89 PoC Similarly, the fetch API does not add a Content-Type header for requests that do not include a Body. Impact Bypass csrf protection implemented with hono csrf middleware.

Published by the source

15 Oct 2024, 17:43 UTC

Last modified by the source

10 Sep 2026, 03:50 UTC

Source last checked

26 Oct 2026, 12:31 UTC

1. Revision 2 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-2234-fmw7-43wr

2. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-2234-fmw7-43wr

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# Patch Next advisory brief: CVE-2024-48913

Advisory: Hono allows bypass of CSRF Middleware by a request without Content-Type header.
IDs: CVE-2024-48913, GHSA-2234-fmw7-43wr
Record: https://patchnext.com/advisories/cve-2024-48913 (revision 2, source checked 26 Oct 2026, 12:31 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 5.9)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: hono 4.6.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- npm hono: affected < 4.6.5; fixed in 4.6.5

## Suggested inspection (read-only)
- `npm ls hono --all`: lists every installed copy and version, including transitive ones. Run in the project root after `npm ci`.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on hono.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GHSA-2234-fmw7-43wr (OSV record GHSA-2234-fmw7-43wr lists affected ranges: npm hono >=0 <4.6.5 (fixed))
- Verified: https://github.com/advisories/GHSA-2234-fmw7-43wr (GitHub-reviewed advisory GHSA-2234-fmw7-43wr lists affected ranges: npm hono >=0 <4.6.5)

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