Node *ContainerNode::childNode(unsigned index) const
{
    unsigned i;
    Node *n = firstChild();
    for (i = 0; n != 0 && i < index; i++)
        n = n->nextSibling();
    return n;
}

This vulnerability category highlights issues in resource management where failures to properly release memory, file handles, or other resources can degrade system performance or enable denial-of-service conditions.