CVE-2026-39408

HIGH

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

Title source: cna

Description

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.

References (3)

[X_Refsource_Confirm] https://github.com/honojs/hono/security/advisories/GHSA-xf4j-xp2r-rqqx

[X_Refsource_Misc] https://github.com/honojs/hono/commit/b470278920fffcfd6d76002755d6db53db827679

View Writeup ZIP pw:eip

[X_Refsource_Misc] https://github.com/honojs/hono/releases/tag/v4.12.12

Scores

CVSS v3 7.5

EPSS 0.0001

EPSS Percentile 1.6%

Attack Vector NETWORK

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

CISA SSVC

Vulnrichment

Exploitation none

Automatable yes

Technical Impact partial

Details

CWE

CWE-22

Status published

Products (3)

hono/hono 4.0.0 - 4.12.11

honojs/hono < 4.12.12

npm/hono 4.0.0 - 4.12.12npm

Published Apr 08, 2026

Tracked Since Apr 08, 2026