Do not fetch external parameter entities
Unless explicitely asked for when validating or replacing entities
with their value. Problem pointed out by Daniel Berrange <berrange@redhat.com>
diff --git a/parser.c b/parser.c
index 9347ac9..c0dea05 100644
--- a/parser.c
+++ b/parser.c
@@ -2598,6 +2598,20 @@
xmlCharEncoding enc;
/*
+ * Note: external parsed entities will not be loaded, it is
+ * not required for a non-validating parser, unless the
+ * option of validating, or substituting entities were
+ * given. Doing so is far more secure as the parser will
+ * only process data coming from the document entity by
+ * default.
+ */
+ if ((entity->etype == XML_EXTERNAL_PARAMETER_ENTITY) &&
+ ((ctxt->options & XML_PARSE_NOENT) == 0) &&
+ ((ctxt->options & XML_PARSE_DTDVALID) == 0) &&
+ (ctxt->validate == 0))
+ return;
+
+ /*
* handle the extra spaces added before and after
* c.f. http://www.w3.org/TR/REC-xml#as-PE
* this is done independently.
