What is CVE-2026-14181?

CVE-2026-14181 is a high-severity vulnerability in @Fastify/middie, classified under CWE-248. CVSS score: 7.5/10. Published 2026-07-01.

How severe is CVE-2026-14181?

High severity. CVSS v3 base score is 7.5 out of 10.

Vulnerability in @Fastify/middie

CVE-2026-14181

@fastify/middie versions 9.1.0 through 9.3.2 fail to guard the URL normalization step used by the standalone engine when incoming request paths contain malformed percent-encoded sequences. Inputs such as an incomplete percent escape or a t…

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

@Fastify/middie — versions 9.1.0, 9.3.3

Weakness classification (CWE)

CWE-248

References

ce714d77-add3-4f53-aff5-83d477b104bb
ce714d77-add3-4f53-aff5-83d477b104bb

Frequently asked questions

What is CVE-2026-14181?: CVE-2026-14181 is a high-severity vulnerability in @Fastify/middie, classified under CWE-248. CVSS score: 7.5/10. Published 2026-07-01.
How severe is CVE-2026-14181?: High severity. CVSS v3 base score is 7.5 out of 10.