Nokogiri: Null Pointer Dereference calling methods on uninitialized wrapper classes
### Summary Nokogiri contains a bug when calling certain methods on allocated-but-uninitialized native wrapper classes that inherit from `Nokogiri::XML::Node`. This caused a NULL pointer dereference that could crash the process. Nokogiri 1.19.4 checks for missing native data pointers and raises a `RuntimeError`. JRuby is not affected. ### Severity The Nokogiri maintainers have evaluated this as low severity. This is only triggered by a programming error. It requires application code to call `.allocate` directly on a native-backed class and then invoke methods on the resulting uninitialized object. It cannot be triggered by untrusted input or through normal use of the public API. ### Mitigation Upgrade to Nokogiri 1.19.4 or later. Avoid calling `.allocate` directly on Nokogiri native-backed classes. Use the documented constructors and factory methods instead. ### Credit This issue was responsibly reported by Zheng Yu from depthfirst.com.
describes (1)
Related CVEs.
| ID | severity | exploitable | ||
|---|---|---|---|---|
| CVE-2026-57434US | high7.5 | — | ||
Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.4, Nokogiri contains a bug when calling certain methods on allocated-but-uninitiali… | ||||
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