Proper return from error-based technique enumeration

lib/techniques/error/use.py

@@ -97,7 +97,9 @@ def __errorFields(expression, expressionFields, expressionFieldsList, expected=N
                 logger.warn(warnMsg)
 
             output = __oneShotErrorUse(expressionReplaced, field)
-            logger.info("retrieved: %s" % output)
+
+            if output is not None:
+                logger.info("retrieved: %s" % output)
 
         if isinstance(num, int):
             expression = origExpr
@@ -145,7 +147,7 @@ def errorUse(expression, expected=None, resumeValue=True, dump=False):
     # entry per time
     # NOTE: I assume that only queries that get data from a table can
     # return multiple entries
-    if " FROM " in expression.upper() and ((Backend.getIdentifiedDbms() not in FROM_TABLE) or (Backend.getIdentifiedDbms() in FROM_TABLE and not expression.upper().endswith(FROM_TABLE[Backend.getIdentifiedDbms()]))) and "EXISTS(" not in expression.upper():
+    if " FROM " in expression.upper() and ((Backend.getIdentifiedDbms() not in FROM_TABLE) or (Backend.getIdentifiedDbms() in FROM_TABLE and not expression.upper().endswith(FROM_TABLE[Backend.getIdentifiedDbms()]))) and "EXISTS(" not in expression.upper() and "(CASE" not in expression.upper():
         limitRegExp = re.search(queries[Backend.getIdentifiedDbms()].limitregexp.query, expression, re.I)
         topLimit = re.search("TOP\s+([\d]+)\s+", expression, re.I)
 
@@ -258,6 +260,9 @@ def errorUse(expression, expected=None, resumeValue=True, dump=False):
                 try:
                     for num in xrange(startLimit, stopLimit):
                         output = __errorFields(expression, expressionFields, expressionFieldsList, expected, num, resumeValue)
+                        if output and isinstance(output, list) and len(output) == 1:
+                            output = output[0]
+
                         outputs.append(output)
 
                 except KeyboardInterrupt:
@@ -270,8 +275,10 @@ def errorUse(expression, expected=None, resumeValue=True, dump=False):
                 debugMsg = "performed %d queries in %d seconds" % (reqCount, duration)
                 logger.debug(debugMsg)
 
-                return outputs
+    if not outputs:
-    else:
+        outputs = __errorFields(expression, expressionFields, expressionFieldsList)
-        return __errorFields(expression, expressionFields, expressionFieldsList)
+
+    if outputs and isinstance(outputs, list) and len(outputs) == 1:
+        outputs = outputs[0]
 
     return outputs

lib/techniques/inband/union/use.py

@@ -254,7 +254,7 @@ def unionUse(expression, direct=False, unescape=True, resetCounter=False, unpack
         reqCount += 1
 
         if kb.misc.start not in content or kb.misc.stop not in content:
-            return
+            return None
 
         # Parse the returned page to get the exact inband
         # sql injection output

plugins/generic/enumeration.py

@@ -267,9 +267,6 @@ class Enumeration:
                     if parsedUser:
                         user = parsedUser.groups()[0]
 
-                if isinstance(user, list):
-                    user = user[0]
-
                 if not user or user in retrievedUsers:
                     continue
 
@@ -539,9 +536,6 @@ class Enumeration:
                 if Backend.getIdentifiedDbms() == DBMS.MYSQL and kb.data.has_information_schema:
                     unescapedUser = unescaper.unescape(user, quote=False)
 
-                if isinstance(user, list):
-                    user = user[0]
-
                 if not user or user in retrievedUsers:
                     continue