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CVE-2021-41098

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

Published: Sep 27, 2021Updated: Nov 21, 2024 Sources: CVE List NVD GHSACWE-611

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 Vector Breakdown

AV:NAC:LPR:NUI:NS:UC:HI:NA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:NPrivileges Required
None
UI:NUser Interaction
None
Scope
S:UScope
Unchanged
Impact
C:HConfidentiality
High
I:NIntegrity
None
A:NAvailability
None

Weaknesses

Affected Products

Attack Graph

Products CVE Techniques Tactics

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Exploitability

1 exploit source identified

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Official Patch Available

MITRE ATT&CK

2 techniques
Collection
Initial Access
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References

and 2 more references View all →

Timeline

Published
Sep 27, 2021
Last Updated
Nov 21, 2024

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