CVE-2026-57436
Medium
Description
Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.4, Nokogiri::XML::Document#root= validated only that the new root was a Nokogiri::XML::Node, allowing a DTD node to be set as the document root. The result is a heap use-after-free during garbage collection or finalization, leading to an invalid memory read or potentially a segfault. This vulnerability is fixed in 1.19.4.
SeverityMedium
CVSS5.3
Exploit probability—
ProductNokogiri
PublishedJun 25, 2026
First seenJun 25, 2026
Weakness typeCWE-416Use after free
How to fix
Update
- nokogiri nokogiri1.19.4 or later
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| nokogiri nokogiri | v < 1.19.4 | 1.19.4 |
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