What is CVE-2026-57438?

CVE-2026-57438 is a medium-severity vulnerability in Nokogiri, classified under Use After Free. CVSS score: 6.6/10. Published 2026-06-25.

How severe is CVE-2026-57438?

Medium severity. CVSS v3 base score is 6.6 out of 10.

Use After Free in Nokogiri

CVE-2026-57438

Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.4, XInclude substitution performed by Nokogiri::XML::Node#do_xinclude replaced each <xi:include> in place, freeing the include node along with…

Vulnerability class: Use-After-Free

EPSS: 0.001 (0.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 6.6 (Medium). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:H.

Affected products

Nokogiri
Sparklemotion Nokogiri — versions < 1.19.4

Weakness classification (CWE)

CWE-416 — Use After Free

References

security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)

Frequently asked questions

What is CVE-2026-57438?: CVE-2026-57438 is a medium-severity vulnerability in Nokogiri, classified under Use After Free. CVSS score: 6.6/10. Published 2026-06-25.
How severe is CVE-2026-57438?: Medium severity. CVSS v3 base score is 6.6 out of 10.