Bug 2554165 (CVE-2026-55862)

Summary: CVE-2026-55862 libupnp: libupnp: Denial of Service via deeply nested XML
Product: [Other] Security Response Reporter: OSIDB Bzimport <bzimport>
Component: vulnerabilityAssignee: Product Security DevOps Team <prodsec-dev>
Status: NEW --- QA Contact:
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Priority: medium    
Version: unspecifiedKeywords: Security
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Hardware: All   
OS: Linux   
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A flaw was found in libupnp. Several Document Object Model (DOM) traversal functions process deeply nested XML structures using unbounded recursion. An unauthenticated attacker on the local network can exploit this flaw by sending a crafted SOAP request containing deeply nested XML, exhausting stack memory. This issue causes the UPnP service to crash, resulting in a Denial of Service (DoS).
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Bug Depends On: 2558158, 2558159    
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Description OSIDB Bzimport 2026-10-16 15:42:37 UTC 
pupnp is an SDK for development of UPnP device and control point applications. Prior to 2.0.0, multiple ixml DOM traversal functions process deeply nested XML with unbounded recursion. The iterative XML parser accepts the document, but ixmlPrintDomTreeRecursive in ixml/src/ixml.c and ixmlNode_getElementsByTagNameRecursive, ixmlNode_getElementsByTagNameNSRecursive, ixmlNode_cloneNodeTreeRecursive, and ixmlNode_isAncestor in ixml/src/node.c recurse over firstChild and nextSibling links. An unauthenticated peer on the local network can supply deeply nested XML through a SOAP request, exhaust a service thread's stack, and crash the UPnP service. This is an incomplete-fix case for CVE-2021-28302 because its remediation converted ixmlNode_free but left these traversal paths recursive. This issue is fixed in 2.0.0.