diff --git a/mysql-test/r/range.result b/mysql-test/r/range.result
index b3324601e47..9ea0dc12a0b 100644
--- a/mysql-test/r/range.result
+++ b/mysql-test/r/range.result
@@ -3087,5 +3087,77 @@ set max_session_mem_used=@tmp_24117;
 deallocate prepare s;
 drop table t0,t1,t2;
 #
+# MDEV-23811: Both disjunct of WHERE condition contain range conditions
+#             for the same index such that the second range condition
+#             fully covers the first one. Additionally one of the disjuncts
+#             contains a range condition for the other index.
+#
+create table t1 (
+pk int primary key auto_increment, a int, b int,
+index idx1(a), index idx2(b)
+);
+insert into t1(a,b) values
+(5,50), (1,10), (3,30), (7,70), (8,80), (4,40), (2,20), (6,60);
+insert into t1(a,b) select a+10, b+100 from t1;
+insert into t1(a,b) select a+20, b+200 from t1;
+insert into t1(a,b) select a+30, b+300 from t1;
+insert into t1(a,b) select a,b from t1;
+analyze table t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+explain select * from t1 where ((a between 3 and 4) and b < 100) or (a between 2 and 5);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where
+select * from t1 where ((a between 3 and 4) and b < 100) or (a between 2 and 5);
+pk	a	b
+7	2	20
+71	2	20
+3	3	30
+67	3	30
+6	4	40
+70	4	40
+1	5	50
+65	5	50
+explain select * from t1 where (a between 2 and 5) or ((a between 3 and 4) and b < 100);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where
+select * from t1 where (a between 2 and 5) or ((a between 3 and 4) and b < 100);
+pk	a	b
+7	2	20
+71	2	20
+3	3	30
+67	3	30
+6	4	40
+70	4	40
+1	5	50
+65	5	50
+explain select * from t1 where (a between 3 and 4) or ((a between 2 and 5) and b < 100);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where
+select * from t1 where (a between 3 and 4) or ((a between 2 and 5) and b < 100);
+pk	a	b
+7	2	20
+71	2	20
+3	3	30
+67	3	30
+6	4	40
+70	4	40
+1	5	50
+65	5	50
+explain select * from t1 where ((a between 2 and 5) and b < 100) or (a between 3 and 4);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where
+select * from t1 where ((a between 2 and 5) and b < 100) or (a between 3 and 4);
+pk	a	b
+7	2	20
+71	2	20
+3	3	30
+67	3	30
+6	4	40
+70	4	40
+1	5	50
+65	5	50
+drop table t1;
+#
 # End of 10.2 tests
 #
diff --git a/mysql-test/r/range_mrr_icp.result b/mysql-test/r/range_mrr_icp.result
index d614a3397ee..55613261ce9 100644
--- a/mysql-test/r/range_mrr_icp.result
+++ b/mysql-test/r/range_mrr_icp.result
@@ -3099,6 +3099,78 @@ set max_session_mem_used=@tmp_24117;
 deallocate prepare s;
 drop table t0,t1,t2;
 #
+# MDEV-23811: Both disjunct of WHERE condition contain range conditions
+#             for the same index such that the second range condition
+#             fully covers the first one. Additionally one of the disjuncts
+#             contains a range condition for the other index.
+#
+create table t1 (
+pk int primary key auto_increment, a int, b int,
+index idx1(a), index idx2(b)
+);
+insert into t1(a,b) values
+(5,50), (1,10), (3,30), (7,70), (8,80), (4,40), (2,20), (6,60);
+insert into t1(a,b) select a+10, b+100 from t1;
+insert into t1(a,b) select a+20, b+200 from t1;
+insert into t1(a,b) select a+30, b+300 from t1;
+insert into t1(a,b) select a,b from t1;
+analyze table t1;
+Table	Op	Msg_type	Msg_text
+test.t1	analyze	status	OK
+explain select * from t1 where ((a between 3 and 4) and b < 100) or (a between 2 and 5);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where; Rowid-ordered scan
+select * from t1 where ((a between 3 and 4) and b < 100) or (a between 2 and 5);
+pk	a	b
+1	5	50
+3	3	30
+6	4	40
+7	2	20
+65	5	50
+67	3	30
+70	4	40
+71	2	20
+explain select * from t1 where (a between 2 and 5) or ((a between 3 and 4) and b < 100);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where; Rowid-ordered scan
+select * from t1 where (a between 2 and 5) or ((a between 3 and 4) and b < 100);
+pk	a	b
+1	5	50
+3	3	30
+6	4	40
+7	2	20
+65	5	50
+67	3	30
+70	4	40
+71	2	20
+explain select * from t1 where (a between 3 and 4) or ((a between 2 and 5) and b < 100);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where; Rowid-ordered scan
+select * from t1 where (a between 3 and 4) or ((a between 2 and 5) and b < 100);
+pk	a	b
+1	5	50
+3	3	30
+6	4	40
+7	2	20
+65	5	50
+67	3	30
+70	4	40
+71	2	20
+explain select * from t1 where ((a between 2 and 5) and b < 100) or (a between 3 and 4);
+id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
+1	SIMPLE	t1	range	idx1,idx2	idx1	5	NULL	11	Using index condition; Using where; Rowid-ordered scan
+select * from t1 where ((a between 2 and 5) and b < 100) or (a between 3 and 4);
+pk	a	b
+1	5	50
+3	3	30
+6	4	40
+7	2	20
+65	5	50
+67	3	30
+70	4	40
+71	2	20
+drop table t1;
+#
 # End of 10.2 tests
 #
 set optimizer_switch=@mrr_icp_extra_tmp;
diff --git a/mysql-test/r/range_vs_index_merge_innodb.result b/mysql-test/r/range_vs_index_merge_innodb.result
index 581f512768c..916c30bb770 100644
--- a/mysql-test/r/range_vs_index_merge_innodb.result
+++ b/mysql-test/r/range_vs_index_merge_innodb.result
@@ -369,7 +369,7 @@ WHERE ((ID < 200) AND (Name LIKE 'Ha%' OR (Country > 'A' AND Country < 'ARG')))
 OR ((ID BETWEEN 100 AND 200) AND 
 (Name LIKE 'Pa%' OR (Population > 103000 AND Population < 104000)));
 id	select_type	table	type	possible_keys	key	key_len	ref	rows	Extra
-1	SIMPLE	City	index_merge	PRIMARY,Population,Country,Name	Name,Population,PRIMARY	39,4,4	NULL	307	Using sort_union(Name,Population,PRIMARY); Using where
+1	SIMPLE	City	range	PRIMARY,Population,Country,Name	PRIMARY	4	NULL	200	Using where
 SELECT * FROM City USE INDEX ()
 WHERE ((ID < 10) AND (Name LIKE 'H%' OR (Country > 'A' AND Country < 'ARG')))
 OR ((ID BETWEEN 100 AND 110) AND 
diff --git a/mysql-test/t/range.test b/mysql-test/t/range.test
index f34ac2049e1..264f7c784ce 100644
--- a/mysql-test/t/range.test
+++ b/mysql-test/t/range.test
@@ -2141,6 +2141,48 @@ set max_session_mem_used=@tmp_24117;
 deallocate prepare s;
 
 drop table t0,t1,t2;
+--echo #
+--echo # MDEV-23811: Both disjunct of WHERE condition contain range conditions
+--echo #             for the same index such that the second range condition
+--echo #             fully covers the first one. Additionally one of the disjuncts
+--echo #             contains a range condition for the other index.
+--echo #
+
+create table t1 (
+  pk int primary key auto_increment, a int, b int,
+  index idx1(a), index idx2(b)
+);
+insert into t1(a,b) values
+  (5,50), (1,10), (3,30), (7,70), (8,80), (4,40), (2,20), (6,60);
+insert into t1(a,b) select a+10, b+100 from t1;
+insert into t1(a,b) select a+20, b+200 from t1;
+insert into t1(a,b) select a+30, b+300 from t1;
+insert into t1(a,b) select a,b from t1;
+
+analyze table t1;
+
+let $q1=
+select * from t1 where ((a between 3 and 4) and b < 100) or (a between 2 and 5);
+eval explain $q1;
+eval $q1;
+
+let $q2=
+select * from t1 where (a between 2 and 5) or ((a between 3 and 4) and b < 100);
+eval explain $q2;
+eval $q2;
+
+let $q3=
+select * from t1 where (a between 3 and 4) or ((a between 2 and 5) and b < 100);
+eval explain $q3;
+eval $q3;
+
+let $q4=
+select * from t1 where ((a between 2 and 5) and b < 100) or (a between 3 and 4);
+eval explain $q4;
+eval $q4;
+
+drop table t1;
+
 --echo #
 --echo # End of 10.2 tests
 --echo #
diff --git a/sql/opt_range.cc b/sql/opt_range.cc
index e933d2af355..798b1f284bc 100644
--- a/sql/opt_range.cc
+++ b/sql/opt_range.cc
@@ -1852,6 +1852,9 @@ SEL_ARG::SEL_ARG(SEL_ARG &arg) :Sql_alloc()
   next_key_part=arg.next_key_part;
   max_part_no= arg.max_part_no;
   use_count=1; elements=1;
+  next= 0;
+  if (next_key_part)
+    ++next_key_part->use_count;
 }
 
 
@@ -9597,10 +9600,11 @@ key_or(RANGE_OPT_PARAM *param, SEL_ARG *key1,SEL_ARG *key2)
 
       if (!tmp->next_key_part)
       {
-        if (key2->use_count)
+	SEL_ARG *key2_next= key2->next;
+	if (key2_shared)
 	{
 	  SEL_ARG *key2_cpy= new SEL_ARG(*key2);
-          if (key2_cpy)
+          if (!key2_cpy)
             return 0;
           key2= key2_cpy;
 	}
@@ -9621,7 +9625,7 @@ key_or(RANGE_OPT_PARAM *param, SEL_ARG *key1,SEL_ARG *key2)
             Move on to next range in key2
           */
           key2->increment_use_count(-1); // Free not used tree
-          key2=key2->next;
+          key2=key2_next;
           continue;
         }
         else