CVE-2026-39408

EUVD-2026-20495 · Published Apr 8, 2026

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.

Technologies

Hono Hono

Weaknesses

CWE-22

CVSS scores

v4.05.9CVSS:4.0/AV:L/AC:H/AT:P/PR:N/UI:N/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
v3.17.5CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

MITRE ATT&CK

Inferred

Where this vulnerability fits in an attack

ReconImpact

Initial Access

T1190Exploit Public-Facing Application

References

https://github.com/honojs/hono/security/advisories/GHSA-xf4j-xp2r-rqqx
https://github.com/honojs/hono/commit/b470278920fffcfd6d76002755d6db53db827679
https://github.com/honojs/hono/releases/tag/v4.12.12
https://nvd.nist.gov/vuln/detail/CVE-2026-39408
https://github.com/honojs/hono

Potentially impacted assets

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