Medium 5.9Published Apr 8, 2026

CVE-2026-39408Hono has a path traversal in toSSG() allows writing files outside the output directory

Updated under an hour ago (Oct 27, 2026, 4:23 AM ET)

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Every CVE for honojs hono

Exploited in the last 30 days

Hono is a Web application framework that provides support for any JavaScript runtime. Prior to 4.12.12, a path traversal issue in toSSG() allows files to be written outside the configured output directory during static site generation. When using dynamic route parameters via ssgParams, specially crafted values can cause generated file paths to escape the intended output directory. This vulnerability is fixed in 4.12.12.

CVSS: 5.9 MEDIUM (v4.0, CNA)CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N
Weakness (CWE): CWE-22
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: GitHub_M
NVD analysis: Analyzed
Record last updated: Apr 10, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

honojs hono honojs:hono (from the name)	before 4.12.12	CNA record
hono hono hono:hono	from 4.0.0 through 4.12.11	NVD

References

References

https://github.com/honojs/hono/security/advisories/GHSA-xf4j-xp2r-rqqx	x-refsource-confirm, exploit, vendor-advisory
https://github.com/honojs/hono/commit/b470278920fffcfd6d76002755d6db53db827679	x-refsource-misc, patch
https://github.com/honojs/hono/releases/tag/v4.12.12	x-refsource-misc, release-notes

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.