9.8

CVE-2026-29045: hono

CVSS: 9.8v3.1CriticalAnalyzed
AliasesGHSA-q5qw-h33p-qvwrCGA-233v-657r-5mmrCGA-2735-wwqr-43gh
Published 04-03-2026Last modified 05-03-2026
Open JSON

Vulnerability summary

CVE-2026-29045 is a critical (CVSS 9.8) vulnerability in hono. EPSS estimates a 0.62% chance of exploitation in the next 30 days, higher than 48.8% of scored vulnerabilities.

Overall risk
70/100
0100
High · default modelHow is this calculated?
CVSS score
9.8/10
010
Critical · v3.1 (NVD)
EPSS score
0.62%
0%100%
Low · +0.12 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 2
CGA-95FQ-H77J-9QC3CVE-2026-6414

Timeline

  1. 04-03-2026
    PublishedVulnerability first disclosed.
  2. 05-03-2026
    Last modifiedVulnerability information updated.

Description

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to version 4.12.4, when using serveStatic together with route-based middleware protections (e.g. app.use('/admin/*', ...)), inconsistent URL decoding allowed protected static resources to be accessed without authorization. The router used decodeURI, while serveStatic used decodeURIComponent. This mismatch allowed paths containing encoded slashes (%2F) to bypass middleware protections while still resolving to the intended filesystem path. This issue has been patched in version 4.12.4.

CVSS metrics

4 scores · 4 sources · 1 version

EPSS trend

Probability

0.62%

Chance of exploitation in the next 30 days

Percentile

49%

Versus all other CVEs

30-day change

+0.12 pp

From 0.50% on 20-09-2026

20-09-202620-10-2026
EPSS score
0.62%

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

Chainguard13 products
  • honoAll versions (No fix recorded)
  • hono-adapter-mqttAll versions (No fix recorded)
  • hono-cliAll versions (No fix recorded)
  • hono-compatAll versions (No fix recorded)
  • hono-service-authAll versions (No fix recorded)
Hono1 product
Honojs1 product
Npm1 product
  • hono< 4.12.4

4 vendors · 16 products

References

5 links