CVE-2021-41098

Improper Restriction of XML External Entity Reference (XXE) in Nokogiri on JRuby

HIGH
7.5
CVSS Score
Published: September 27, 2021 at 07:35 PM UTC
Updated: June 17, 2026 at 04:07 AM UTC
2 products affected across 2 vendorsNokogiriNokogiri

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Severity
HIGH7.5
Exploit prediction
EPSS 1%

Description

Nokogiri is a Rubygem providing HTML, XML, SAX, and Reader parsers with XPath and CSS selector support. In Nokogiri v1.12.4 and earlier, on JRuby only, the SAX parser resolves external entities by default. Users of Nokogiri on JRuby who parse untrusted documents using any of these classes are affected: Nokogiri::XML::SAX::Parse, Nokogiri::HTML4::SAX::Parser or its alias Nokogiri::HTML::SAX::Parser, Nokogiri::XML::SAX::PushParser, and Nokogiri::HTML4::SAX::PushParser or its alias Nokogiri::HTML::SAX::PushParser. JRuby users should upgrade to Nokogiri v1.12.5 or later to receive a patch for this issue. There are no workarounds available for v1.12.4 or earlier. CRuby users are not affected.

Affected

Our own answer: ranges merged, affected separated from platform-only, with confidence and review flags.

v < 1.12.5
Affected range stops below 1.12.5, so it looks safe — our inference, not a vendor statement
v < 1.12.5
Affected range stops below 1.12.5, so it looks safe — our inference, not a vendor statement

Remediation

No guide yet

No remediation guidance has been written for this CVE yet. What the record does show:

CVSS

Attack Vector
NETWORK
Complexity
LOW
Privileges
NONE
User Interaction
NONE
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
NONE
Availability
NONE
Vector?

Quick Info

StatusMODIFIED
CWE
CWE-611

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