High severity · published Jun 25, 2026
CVE-2026-57434
Nokogiri: Null Pointer Dereference calling methods on uninitialized wrapper classes
7.5
CVSS
0.5%
EPSS
No
On KEV
Description
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-uninitialized native wrapper classes that inherit from Nokogiri::XML::Node. This caused a NULL pointer dereference that could crash the process. This vulnerability is fixed in 1.19.4.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
High
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.5% · higher than 40% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
NO
nokogiri · sparklemotion
< 1.19.4 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-57434
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-57434
Mitigation
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-9cv2-cfxc-v4v2
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