Medium 6.3Published Apr 8, 2026

CVE-2026-39409Hono has incorrect IP matching in ipRestriction() for IPv4-mapped IPv6 addresses

Updated under an hour ago (Oct 26, 2026, 2:20 PM ET)

Does this affect you?

It affects honojs hono and 1 other product. Add what you run to find out whether that includes you.

No exploitation reported and no EPSS estimate yet.

Do this next

Start free and add your stack

Free account, 1 product

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, ipRestriction() does not canonicalize IPv4-mapped IPv6 client addresses (e.g. ::ffff:127.0.0.1) before applying IPv4 allow or deny rules. In environments such as Node.js dual-stack, this can cause IPv4 rules to fail to match, leading to unintended authorization behavior. This vulnerability is fixed in 4.12.12.

CVSS: 6.3 MEDIUM (v4.0, CNA)CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N
Weakness (CWE): CWE-180
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 8, 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	through 4.12.11	NVD

References

References

https://github.com/honojs/hono/security/advisories/GHSA-xpcf-pg52-r92g	x-refsource-confirm, vendor-advisory
https://github.com/honojs/hono/commit/48fa2233bc092f650119f42df043050737cabf39	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.