diff --git a/lib/core/agent.py b/lib/core/agent.py
index 10d518a2f..1f8e8eca7 100644
--- a/lib/core/agent.py
+++ b/lib/core/agent.py
@@ -328,7 +328,7 @@ class Agent:
         if not Backend.getDbms():
             return fields
 
-        if fields.startswith("(CASE"):
+        if fields.startswith("(CASE") or fields.startswith("SUBSTR"):
             nulledCastedConcatFields = fields
         else:
             fields = fields.replace(", ", ",")
@@ -368,9 +368,12 @@ class Agent:
         fieldsSelectFrom = re.search("\ASELECT%s\s+(.+?)\s+FROM\s+" % prefixRegex, query, re.I)
         fieldsExists = re.search("EXISTS(.*)", query, re.I)
         fieldsSelect = re.search("\ASELECT%s\s+(.*)" % prefixRegex, query, re.I)
+        fieldsSubstr = re.search("\ASUBSTR", query, re.I)
         fieldsNoSelect = query
 
-        if fieldsExists:
+        if fieldsSubstr:
+            fieldsToCastStr = query
+        elif fieldsExists:
             fieldsToCastStr = fieldsSelect.groups()[0]
         elif fieldsSelectTop:
             fieldsToCastStr = fieldsSelectTop.groups()[0]
@@ -386,7 +389,7 @@ class Agent:
             fieldsToCastStr = fieldsNoSelect
 
         # Function
-        if re.search("\A\w+\(.*\)", fieldsToCastStr, re.I) or fieldsSelectCase:
+        if re.search("\A\w+\(.*\)", fieldsToCastStr, re.I) or fieldsSelectCase or fieldsSubstr:
             fieldsToCastList = [fieldsToCastStr]
         else:
             fieldsToCastList = fieldsToCastStr.replace(", ", ",")
diff --git a/lib/takeover/udf.py b/lib/takeover/udf.py
index 93d7e13fe..ea0771e62 100644
--- a/lib/takeover/udf.py
+++ b/lib/takeover/udf.py
@@ -51,8 +51,8 @@ class UDF:
     def __checkExistUdf(self, udf):
         logger.info("checking if UDF '%s' already exist" % udf)
 
-        query  = agent.forgeCaseStatement(queries[Backend.getIdentifiedDbms()].check_udf.query % (udf, udf))
-        exists = inject.getValue(query, resumeValue=False, unpack=False, charsetType=2)
+        query = agent.forgeCaseStatement(queries[Backend.getIdentifiedDbms()].check_udf.query % (udf, udf))
+        exists = inject.getValue(query, resumeValue=False, charsetType=2)
 
         if exists == "1":
             return True
diff --git a/plugins/generic/enumeration.py b/plugins/generic/enumeration.py
index a5df1f77d..7adcfb512 100644
--- a/plugins/generic/enumeration.py
+++ b/plugins/generic/enumeration.py
@@ -142,7 +142,7 @@ class Enumeration:
             query = queries[Backend.getIdentifiedDbms()].is_dba.query
 
         query = agent.forgeCaseStatement(query)
-        isDba = inject.getValue(query, unpack=False, charsetType=1)
+        isDba = inject.getValue(query, charsetType=1)
 
         if user is None:
             kb.data.isDba = isDba
diff --git a/plugins/generic/misc.py b/plugins/generic/misc.py
index 695c6053c..e73b35972 100644
--- a/plugins/generic/misc.py
+++ b/plugins/generic/misc.py
@@ -74,7 +74,7 @@ class Miscellaneous:
         if conf.direct:
             query = "SELECT %s" % query
 
-        kb.bannerFp["dbmsVersion"] = inject.getValue(query, unpack=False)
+        kb.bannerFp["dbmsVersion"] = inject.getValue(query)
         kb.bannerFp["dbmsVersion"] = kb.bannerFp["dbmsVersion"].replace(",", "").replace("-", "").replace(" ", "")
 
     def delRemoteFile(self, tempFile):
diff --git a/xml/queries.xml b/xml/queries.xml
index 141b1dd8a..9efa5e7ba 100644
--- a/xml/queries.xml
+++ b/xml/queries.xml
@@ -95,7 +95,7 @@
         -->
         <timedelay query="SELECT PG_SLEEP(%d)" query2="SELECT 'sqlmap' WHERE exists(SELECT * FROM generate_series(1, 300000%d))" query3="CREATE OR REPLACE FUNCTION sleep(int) RETURNS int AS '/lib/libc.so.6', 'sleep' language 'C' STRICT; SELECT sleep(%d)"/>
         <substring query="SUBSTR((%s)::text, %d, %d)"/>
-        <case query="SELECT (CASE WHEN (%s) THEN 1 ELSE 0 END)"/>
+        <case query="SELECT (CASE WHEN (%s) THEN '1' ELSE '0' END)"/>
         <inference query="ASCII(SUBSTR((%s)::text, %d, 1)) > %d"/>
         <banner query="SELECT VERSION()"/>
         <current_user query="SELECT CURRENT_USER"/>