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TI-2026-28389 Aliases CVE-2026-39407GHSA-wmmm-f939-6g9c

Hono has a middleware bypass via repeated slashes in serveStatic

Priority LOW 30CWE-22Published · Updated

Key facts

Attack vector
Network
Privileges required
None
User interaction
None
Attack complexity
Low
Impact type
Information disclosure
Confidentiality · integrity · availability
Low · None · None
Fix status
Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA and GitHub. Impact type from CWE-22 and the CVSS impact.

Summary

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.12, a path handling inconsistency in serveStatic allows protected static files to be accessed by using repeated slashes (//) in the request path. When route-based middleware (e.g., /admin/*) is used for authorization, the router may not match paths containing repeated slashes, while serveStatic resolves them as normalized paths. This can lead to a middleware bypass. This vulnerability is fixed in 4.12.12.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00467 40th percentileScored 2026-11-07
Fix Fixed hono (honojs): 4.12.12hono (npm): 4.12.12

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
Yes
Technical impact
Partial

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
honojshonobefore 4.12.124.12.12Patch availableCNA
—hono (npm)before 4.12.124.12.12Patch availableGHSA-wmmm-f939-6g9c
  • hono Vendorhonojs Affected before 4.12.12 Fixed in 4.12.12 Patch available CNA
  • hono (npm) Vendor— Affected before 4.12.12 Fixed in 4.12.12 Patch available GHSA-wmmm-f939-6g9c

CPE configurations NVD · 1

CPEVersionsRoleVendor
cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:*up to 4.12.11Vulnerablehonojs
  • cpe:2.3:a:hono:hono:*:*:*:*:*:node.js:*:* Versions up to 4.12.11 Vulnerable ·honojs

Remediation

  • Fix · CNA hono (honojs) Fixed in 4.12.12
  • Fix · GHSA-wmmm-f939-6g9c hono (npm) Fixed in 4.12.12 Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-39407
  2. 2026-10-03 Alias added: GHSA-wmmm-f939-6g9c

References

Patch 1

Advisory 2

Other 2

  • TI-2024-21741 Hono vulnerable to Restricted Directory Traversal in serveStatic with deno CVSS 3.1MEDIUM 5.3
  • TI-2024-32610 Hono vulnerable to bypass of CSRF Middleware by a request without Content-Type header. CVSS 3.1MEDIUM 5.9
  • TI-2024-29381 Hono CSRF middleware can be bypassed using crafted Content-Type header CVSS 3.1MEDIUM 5.0
  • TI-2026-23190 Hono: Arbitrary file access via serveStatic vulnerability CVSS 3.1CRITICAL 9.8
  • TI-2026-22076 Hono is Vulnerable to Authentication Bypass by IP Spoofing in AWS Lambda ALB conninfo CVSS 3.1HIGH 8.2
  • TI-2026-18334 JWT algorithm confusion in Hono JWK Auth Middleware when JWK lacks "alg" (untrusted header.alg fallback) CVSS 3.1HIGH 8.2
See all 33 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences