GHSA-9cv2-cfxc-v4v2Low▾ SunlitNokogiri: Null Pointer Dereference calling methods on uninitialized wrapper classes
▾ Sunlit zone — Low / medium · no exploitation signal
impact 13.8 · likelihood 0 · exploitation 0
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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.
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.
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.
This issue was responsibly reported by Zheng Yu from depthfirst.com.
nokogiri < 1.19.4Upgrade to a patched release:
nokogiri 1.19.4Connected by shared product, vendor, weakness, or advisory.
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