# CVE-2026-126355: Hono csrf() middleware bypass via hyperlink auditing

Source: https://junglewise.ai/threats/cve-2026-126355-hono-csrf-does-not-check-requests-sent-by-hyperlink-auditing  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-11-13. Updated: 2026-11-12  
License: CC BY 4.0 with a link back

CVE-2026-126355 · Severity: medium · CVSS 5.3 · Published 2026-11-13

Hono is a web framework with built-in CSRF protection. The csrf() middleware fails to validate requests sent by Chromium's hyperlink auditing feature (text/ping content type), allowing an attacker on a malicious website to trigger state-changing actions in a victim's application without their knowledge—such as logging them out, deleting resources, or changing settings.

Technologies: [Hono](https://junglewise.ai/threats/technologies/hono-hono), [hono (npm)](https://junglewise.ai/threats/technologies/hono). Vendors: [Hono](https://junglewise.ai/threats/vendors/hono), [npm](https://junglewise.ai/threats/vendors/npm).

## Quick answers

**Is CVE-2026-126355 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-126355 being exploited in the wild.

**How severe is CVE-2026-126355?** Medium severity, with a CVSS score of 5.3, published 13 November 2026.

**Which products and versions are affected?** Hono <UNKNOWN>; hono (npm) < 4.13.16, SEMVER:introduced=0,fixed=4.13.16.

**Is there a fix for CVE-2026-126355?** Yes. hono (npm): upgrade to 4.13.16 or later. Until then: Reject requests with Content-Type: text/ping in a middleware registered before csrf(), or set session cookies with SameSite=Strict.</anigation>
<parameter name="timeline">[{"kind": "disclosed", "at": "2026-11-12"}] Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-126355 attacked?** It is attacked over the network, in a software library.

**Am I affected by CVE-2026-126355?** Check whether you run Hono or hono (npm) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- hono (npm): upgrade to 4.13.16 or later

  ```sh
  npm install hono@4.13.16
  ```


Reject requests with Content-Type: text/ping in a middleware registered before csrf(), or set session cookies with SameSite=Strict.</anigation>
<parameter name="timeline">[{"kind": "disclosed", "at": "2026-11-12"}]

## Technical details

The csrf() middleware only validates Origin and Sec-Fetch-Site headers for requests with content types that HTML forms can produce (application/x-www-form-urlencoded, multipart/form-data, text/plain); it skips validation for other content types assuming they require CORS preflight. Chromium's hyperlink auditing bypasses this assumption by sending credentialed POST requests with Content-Type: text/ping without preflight, allowing cross-origin CSRF. The vulnerability affects only actions whose effect is independent of the request body, and requires the user's cookies to be sent (default SameSite=Lax permits this from same-site or SameSite=None cookies).

## Affected products

- Hono Hono <UNKNOWN>

## Identifiers

- CVE-2026-126355
- GHSA-46wx-v44x-9hh2

## Related threats

- [Hono: `css` helper does not escape a closing tag split between the template and an interpolated value, allowing HTML injection](https://junglewise.ai/threats/cve-2026-126359-hono-css-helper-does-not-escape-a-closing-tag-split-between-the)
- [Hono RegExpRouter middleware bypass via wildcard matching](https://junglewise.ai/threats/cve-2026-126358-hono-regexprouter-skips-wildcard-middleware-for-some-route-sets)
- [Hono mount() path traversal bypasses middleware scoping](https://junglewise.ai/threats/cve-2026-126357-hono-mount-and-app-mount-can-forward-a-path-that-bypasses)
- [Hono validator form multipart/form-data parameter bypass](https://junglewise.ai/threats/cve-2026-126356-hono-validator-form-skips-validation-for-multipart-form-data)
- [Hono serveStatic authorization bypass via double percent-decoding](https://junglewise.ai/threats/cve-2026-111757-hono-is-a-web-application-framework-that-provides-support-for)