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Vulnerability record · CVE-2021-41098 · published 27 September 2021

CVE-2021-41098: Nokogiri xml external entity (xxe) vulnerability

Nokogiri · Nokogiri

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.

7.5 CVSS 3.1 High EPSS 1.4% · top 27.7% CWE-611 · XML external entity (XXE)
7.5CVSS 3.1 base score, v2 5.0
1.4%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

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.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/sparklemotion/nokogiri/commit/5bf729ff3cc84709ee3c3248c981584088bf9f6d PatchThird Party Advisory
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-2rr5-8q37-2w7h Third Party Advisory
https://github.com/sparklemotion/nokogiri/commit/5bf729ff3cc84709ee3c3248c981584088bf9f6d PatchThird Party Advisory
https://github.com/sparklemotion/nokogiri/security/advisories/GHSA-2rr5-8q37-2w7h Third Party Advisory

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Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-41098), CISA KEV, FIRST EPSS (scores of 2026-09-26). This page is refreshed as NVD updates the record.