Bug 2526858 (CVE-2026-83616)

Summary: CVE-2026-83616 xmldom: xmldom: XML Structure Injection via Unvalidated Processing Instruction Targets
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, akhatavk, alizardo, aos-team-art-private, asdas, cdrage, dpaolell, gmalinko, janstey, jchui, jdelft, jhe, jupierce, ktsao, lchilton, lgarciaa, mbiarnes, nboldt, oaljalju, pdelbell, ppalepu, ppostler, prdhamdh, psrna, rhel-process-autobot, rstepani, rushinde, sfeifer, sghai, sidsharm, suppawar, vlaad, watson-tool-maintainers
Target Milestone: ---Keywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in xmldom, a JavaScript module for parsing and serializing XML. An attacker can exploit a vulnerability in how processing instructions are handled to inject arbitrary XML structures. This occurs because the software fails to properly validate input, allowing special characters to bypass security checks. Successful exploitation could lead to data manipulation or other integrity impacts within applications processing the affected XML.
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oVirt Team: --- RHEL 7.3 requirements from Atomic Host:
Cloudforms Team: --- Target Upstream Version:
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Bug Depends On: 2528030, 2528031, 2528033, 2528034, 2528035, 2528036, 2528029, 2528032    
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Description OSIDB Bzimport 2026-09-01 15:15:45 UTC 
xmldom is a pure JavaScript W3C standard-based (XML DOM Level 2 Core) DOMParser and XMLSerializer module. Prior to @xmldom/xmldom versions 0.8.15 and 0.9.12, and in xmldom version 0.6.0 and earlier, Document.createProcessingInstruction(target, data) in lib/dom.js accepts an unvalidated target, while the requireWellFormed: true serializer checks only for a colon and the reserved case-insensitive xml name on 0.9.x and performs no target check on 0.8.x. Because serialization emits <?target data?>, a target containing >, ?, whitespace, or another invalid XML-name character can break the processing-instruction boundary and inject XML structure. This issue is fixed in @xmldom/xmldom versions 0.8.15 and 0.9.12; no fixed version is available for xmldom.