CVE-2026-111757: Hono serveStatic middleware bypass via double decoding

CVE-2026-111757 · Severity: medium · CVSS 5.3 · Published 2026-10-13

Hono is a web framework used to build HTTP applications. A vulnerability in its serveStatic static file serving component allows unauthenticated attackers to bypass authentication or authorization middleware by sending specially crafted URLs that are decoded twice. This could expose protected files to unauthorized access.

Technologies: Hono, hono (npm). Vendors: Hono, npm.

Quick answers

Is CVE-2026-111757 exploited in the wild?
No. Junglewise Threat Intelligence has no report of CVE-2026-111757 being exploited in the wild.
How severe is CVE-2026-111757?
Medium severity, with a CVSS score of 5.3, published 13 October 2026.
Which products and versions are affected?
Hono 4.12.4 before 4.13.11; hono (npm) SEMVER:introduced=4.12.4,fixed=4.13.11.
Is there a fix for CVE-2026-111757?
Yes. hono (npm): upgrade to 4.13.11 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-111757 attacked?
It is attacked over the network.
Am I affected by CVE-2026-111757?
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 4.13.11 or later
    npm install hono@4.13.11

Technical details

The serveStatic component decodes the request path a second time after Hono's router has already decoded it once. By sending a malformed percent-encoded path, an attacker can cause the router to match the encoded form while serveStatic resolves the decoded form, bypassing middleware mounted on static paths. This affects applications that use middleware (such as authentication) to protect parts of their static file directories.

Affected products

  • Hono Hono 4.12.4 before 4.13.11

Identifiers

  • CVE-2026-111757
  • CVE-2026-109955
  • GHSA-5r4p-p66f-jhc7

Timeline

  • 2026-09-29: disclosed: GHSA-5r4p-p66f-jhc7 published
  • 2026-10-13: advisory: CVE-2026-109955 published

References

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