CVE-2026-55862 pupnp: Incomplete fix for CVE-2021-28302: recursive DOM functions cause stack overflow
An unauthenticated attacker can crash the UPnP service by sending deeply nested XML, causing a stack overflow in recursive DOM functions.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-55862?
CVE-2026-55862 is a medium-severity denial of service vulnerability in pupnp, published on 16 Oct 2026. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
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.
Weakness: CWE-674
Which versions are affected by CVE-2026-55862?
It affects 1 product.
Products include Pupnp Project Pupnp.
How do I fix CVE-2026-55862?
Upgrade to a fixed version.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2026-55862 being exploited?
It is not confirmed as exploited in the wild, but public exploit code for CVE-2026-55862 exists.
Other vulnerabilities in pupnp
- CVE-2021-29462 DNS rebinding in pupnp
- CVE-2026-57486 pupnp: NULL pointer dereference in ixmlNode_compare crashes on non-namespaced attributes
- CVE-2026-57487 libupnp chunked HTTP bodies can bypass g_maxContentLength and be fully buffered
- CVE-2026-77630 pupnp: Denial of service via blocking DNS resolution in parse_uri()/GENA callback parsing
- CVE-2021-28302 Denial of service in n/a
Sources
Also known as DEBIAN-CVE-2026-55862, GHSA-25cx-xv8x-j247, UBUNTU-CVE-2026-55862.