diff --git a/nselib/drda.lua b/nselib/drda.lua
index d1a940d76..a896d3201 100644
--- a/nselib/drda.lua
+++ b/nselib/drda.lua
@@ -767,7 +767,7 @@ DB2Socket = {
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data
diff --git a/nselib/giop.lua b/nselib/giop.lua
index 1e20ef8aa..0843ab584 100644
--- a/nselib/giop.lua
+++ b/nselib/giop.lua
@@ -468,7 +468,7 @@ Socket =
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data
diff --git a/nselib/informix.lua b/nselib/informix.lua
index f1ce41a70..5b5691aa7 100644
--- a/nselib/informix.lua
+++ b/nselib/informix.lua
@@ -177,7 +177,7 @@ Socket =
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data
diff --git a/nselib/iscsi.lua b/nselib/iscsi.lua
index 0f7265cd9..b55d42fb1 100644
--- a/nselib/iscsi.lua
+++ b/nselib/iscsi.lua
@@ -513,7 +513,7 @@ Socket =
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data
diff --git a/nselib/nrpc.lua b/nselib/nrpc.lua
index a0b752891..dbdf829c2 100644
--- a/nselib/nrpc.lua
+++ b/nselib/nrpc.lua
@@ -125,7 +125,7 @@ DominoSocket =
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data
diff --git a/nselib/tns.lua b/nselib/tns.lua
index 37f0ce0e6..4db70f68c 100644
--- a/nselib/tns.lua
+++ b/nselib/tns.lua
@@ -1205,7 +1205,7 @@ TNSSocket =
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data
diff --git a/nselib/vnc.lua b/nselib/vnc.lua
index 533d81979..09564a27d 100644
--- a/nselib/vnc.lua
+++ b/nselib/vnc.lua
@@ -366,7 +366,7 @@ VNCSocket =
 	
 		if ( #self.Buffer < count ) then
 			status, data = self.Socket:receive_bytes( count - #self.Buffer )
-			if ( not(status) ) then
+			if ( not(status) or #data < count - #self.Buffer ) then
 				return false, data
 			end
 			self.Buffer = self.Buffer .. data