5.3

CVE-2026-39407: hono Path Traversal

CVSS: 5.3v3.1MediumAnalyzed
AliasesCGA-8cq3-q6wq-6xqpCGA-pm6m-54m9-f92hGHSA-wmmm-f939-6g9c
Published 08-04-2026Last modified 08-04-2026
Open JSON

Vulnerability summary

CVE-2026-39407 is a medium (CVSS 5.3) Path Traversal vulnerability in hono. EPSS estimates a 0.45% chance of exploitation in the next 30 days, higher than 37.8% of scored vulnerabilities.

Overall risk
21/100
0100
Low · default modelHow is this calculated?
CVSS score
5.3/10
010
Medium · v3.1 (CVE.org)
EPSS score
0.45%
0%100%
Low · -0.01 pp in 30 days
KEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded

Advisory lineage

Upstream 0 · Downstream 0 · Related 1
CGA-F5QQ-7G8R-H66W

Timeline

  1. 08-04-2026
    PublishedVulnerability first disclosed.
  2. 08-04-2026
    Last modifiedVulnerability information updated.

Description

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.

CVSS metrics

5 scores · 5 sources · 1 version

EPSS trend

Probability

0.45%

Chance of exploitation in the next 30 days

Percentile

38%

Versus all other CVEs

30-day change

-0.01 pp

From 0.46% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.45%

Known exploited

Compare KEV catalogs

Not in any of the 3 tracked catalogs.

Public exploits

0 found

No public exploits indexed.

Weaknesses

CWE · root cause

Affected systems

Chainguard20 products
  • gemini-cli< 0.37.0-r0
  • honoAll versions (No fix recorded)
  • hono-adapter-mqttAll versions (No fix recorded)
  • hono-cliAll versions (No fix recorded)
  • hono-compatAll versions (No fix recorded)
Hono1 product
Honojs1 product
Npm1 product
  • hono< 4.12.12
Wolfi1 product
  • langfuse-3-worker< 3.164.0-r5

5 vendors · 24 products

References

6 links