Juraj Somorovsky reported that certain XML parsers/servers are affected by the
same, or similar, flaw as the hash table collisions CPU usage denial of
service.  Sending a specially crafted message to an XML service can result in
longer processing time, which could lead to a denial of service.  It is
reported that this attack on XML can be applied on different XML nodes (such as
entities, element attributes, namespaces, various elements in the XML security,
etc.).

xmltex is written in TeX. xmltex appears to use the "group" array(ish) type to
store XML elements however it is unclear if this is vulnerable, it needs 
investigation.