CVE-2026-57236

Nokogiri is an open source XML and HTML library for the Ruby programming language. Prior to 1.19.4, calling Document#encoding= with an invalid encoding (e.g., a non-string, or a string containing a null byte) raises an exception, but only after freeing the document's current encoding string without replacing it. The document is left referencing freed memory, so the next call to Document#encoding reads invalid memory, which can cause a segfault or leak freed bytes into a Ruby String. Affects the CRuby (libxml2) implementation only; JRuby is not affected. This vulnerability is fixed in 1.19.4.

CVSS v3 8.2 HIGH

8.2^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 4.2

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-5v8h-3h3q-446p	Mitigation Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:nokogiri:nokogiri:*:*:*:*:*:ruby:*:*

History

26 Jun 2026, 13:32

Type	Values Removed	Values Added
CVSS	v2 : ~~unknown~~ v3 : ~~unknown~~	v2 : unknown v3 : 8.2
First Time		Nokogiri Nokogiri nokogiri
References	~~() https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-5v8h-3h3q-446p -~~	() https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-5v8h-3h3q-446p - Mitigation, Vendor Advisory
CPE		cpe:2.3:a:nokogiri:nokogiri::::::ruby::*

25 Jun 2026, 15:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-25 15:16

Updated : 2026-06-26 13:32

NVD link : CVE-2026-57236

Mitre link : CVE-2026-57236

CVE.ORG link : CVE-2026-57236

JSON object : View

Products Affected

nokogiri

nokogiri

CWE

CWE-416

Use After Free

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