Bug 2526848 (CVE-2026-83617)

Summary: CVE-2026-83617 @xmldom/xmldom: xmldom: XML injection via embedded line terminator in element/attribute names
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security <prodsec-ir-bot>
Status: NEW --- QA Contact:
Severity: high Docs Contact:
Priority: high    
Version: unspecifiedCC: abarbaro, alizardo, cdrage, gmalinko, janstey, jchui, jhe, ktsao, lchilton, nboldt, oaljalju, pdelbell, psrna, rhel-process-autobot, rstepani, rushinde, sfeifer, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in the @xmldom/xmldom library. The requireWellFormed validation for XML element and attribute names can be bypassed by embedding specific line terminator characters. This allows an attacker to inject malformed XML into the document, potentially leading to XML injection vulnerabilities and bypassing security checks designed to prevent such issues.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
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Bug Depends On: 2536913, 2536914, 2536915, 2536918, 2536916, 2536919    
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Description OSIDB Bzimport 2026-09-01 15:13:12 UTC 
xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. From 0.9.11 until 0.9.12, the requireWellFormed: true element and attribute name checks use the anchored QName_exact expression produced by reg() in lib/grammar.js, which inherits the multiline flag. A name with a valid first line followed by U+000A, U+000D, U+2028, or U+2029 and breakout markup therefore passes validation and is emitted verbatim in element start and end tags or attribute names. This bypasses the strict-serialization checks introduced for the earlier element-name and attribute-name injection advisories, while the default serialization path remains outside the strict guarantee. This issue is fixed in @xmldom/xmldom version 0.9.12.