diff --git a/src/backend/columnar/cstore_fdw.c b/src/backend/columnar/cstore_fdw.c
index e7b1a76b8..97e6f5a3c 100644
--- a/src/backend/columnar/cstore_fdw.c
+++ b/src/backend/columnar/cstore_fdw.c
@@ -78,6 +78,7 @@
 #include "columnar/cstore.h"
 #include "columnar/cstore_fdw.h"
 #include "columnar/cstore_version_compat.h"
+#include "distributed/citus_safe_lib.h"
 
 /* table containing information about how to partition distributed tables */
 #define CITUS_EXTENSION_NAME "citus"
@@ -474,8 +475,8 @@ CStoreProcessCopyCommand(CopyStmt *copyStatement, const char *queryString,
 
 	if (completionTag != NULL)
 	{
-		snprintf(completionTag, COMPLETION_TAG_BUFSIZE, "COPY " UINT64_FORMAT,
-				 processedCount);
+		SafeSnprintf(completionTag, COMPLETION_TAG_BUFSIZE, "COPY " UINT64_FORMAT,
+					 processedCount);
 	}
 }
 
diff --git a/src/backend/columnar/cstore_metadata_tables.c b/src/backend/columnar/cstore_metadata_tables.c
index f23aaba2d..301dd0c91 100644
--- a/src/backend/columnar/cstore_metadata_tables.c
+++ b/src/backend/columnar/cstore_metadata_tables.c
@@ -10,6 +10,8 @@
 
 #include "postgres.h"
 
+#include "safe_lib.h"
+
 #include "columnar/cstore.h"
 #include "columnar/cstore_version_compat.h"
 
@@ -885,12 +887,14 @@ DatumToBytea(Datum value, Form_pg_attribute attrForm)
 		}
 		else
 		{
-			memcpy(VARDATA(result), DatumGetPointer(value), attrForm->attlen);
+			memcpy_s(VARDATA(result), datumLength + VARHDRSZ,
+					 DatumGetPointer(value), attrForm->attlen);
 		}
 	}
 	else
 	{
-		memcpy(VARDATA(result), DatumGetPointer(value), datumLength);
+		memcpy_s(VARDATA(result), datumLength + VARHDRSZ,
+				 DatumGetPointer(value), datumLength);
 	}
 
 	return result;
@@ -909,7 +913,8 @@ ByteaToDatum(bytea *bytes, Form_pg_attribute attrForm)
 	 * after the byteaDatum is freed.
 	 */
 	char *binaryDataCopy = palloc0(VARSIZE_ANY_EXHDR(bytes));
-	memcpy(binaryDataCopy, VARDATA_ANY(bytes), VARSIZE_ANY_EXHDR(bytes));
+	memcpy_s(binaryDataCopy, VARSIZE_ANY_EXHDR(bytes),
+			 VARDATA_ANY(bytes), VARSIZE_ANY_EXHDR(bytes));
 
 	return fetch_att(binaryDataCopy, attrForm->attbyval, attrForm->attlen);
 }
diff --git a/src/backend/columnar/cstore_reader.c b/src/backend/columnar/cstore_reader.c
index 8818baf78..4faf2562c 100644
--- a/src/backend/columnar/cstore_reader.c
+++ b/src/backend/columnar/cstore_reader.c
@@ -16,6 +16,8 @@
 
 #include "postgres.h"
 
+#include "safe_lib.h"
+
 #include "access/nbtree.h"
 #include "catalog/pg_am.h"
 #include "commands/defrem.h"
@@ -1025,7 +1027,7 @@ ReadFromSmgr(Relation rel, uint64 offset, uint32 size)
 		PageHeader phdr = (PageHeader) page;
 
 		uint32 to_read = Min(size - read, phdr->pd_upper - addr.offset);
-		memcpy(resultBuffer->data + read, page + addr.offset, to_read);
+		memcpy_s(resultBuffer->data + read, size - read, page + addr.offset, to_read);
 		ReleaseBuffer(buffer);
 		read += to_read;
 	}
diff --git a/src/backend/columnar/cstore_writer.c b/src/backend/columnar/cstore_writer.c
index dcaf5d122..735024fbf 100644
--- a/src/backend/columnar/cstore_writer.c
+++ b/src/backend/columnar/cstore_writer.c
@@ -16,6 +16,8 @@
 
 #include "postgres.h"
 
+#include "safe_lib.h"
+
 #include "access/nbtree.h"
 #include "catalog/pg_am.h"
 #include "miscadmin.h"
@@ -354,7 +356,7 @@ WriteToSmgr(Relation rel, uint64 logicalOffset, char *data, uint32 dataLength)
 		START_CRIT_SECTION();
 
 		uint64 to_write = Min(phdr->pd_upper - phdr->pd_lower, remaining);
-		memcpy(page + phdr->pd_lower, data, to_write);
+		memcpy_s(page + phdr->pd_lower, phdr->pd_upper - phdr->pd_lower, data, to_write);
 		phdr->pd_lower += to_write;
 
 		MarkBufferDirty(buffer);
@@ -561,13 +563,15 @@ SerializeSingleDatum(StringInfo datumBuffer, Datum datum, bool datumTypeByValue,
 		}
 		else
 		{
-			memcpy(currentDatumDataPointer, DatumGetPointer(datum), datumTypeLength);
+			memcpy_s(currentDatumDataPointer, datumBuffer->maxlen - datumBuffer->len,
+					 DatumGetPointer(datum), datumTypeLength);
 		}
 	}
 	else
 	{
 		Assert(!datumTypeByValue);
-		memcpy(currentDatumDataPointer, DatumGetPointer(datum), datumLength);
+		memcpy_s(currentDatumDataPointer, datumBuffer->maxlen - datumBuffer->len,
+				 DatumGetPointer(datum), datumLength);
 	}
 
 	datumBuffer->len += datumLengthAligned;
@@ -714,7 +718,7 @@ DatumCopy(Datum datum, bool datumTypeByValue, int datumTypeLength)
 	{
 		uint32 datumLength = att_addlength_datum(0, datumTypeLength, datum);
 		char *datumData = palloc0(datumLength);
-		memcpy(datumData, DatumGetPointer(datum), datumLength);
+		memcpy_s(datumData, datumLength, DatumGetPointer(datum), datumLength);
 
 		datumCopy = PointerGetDatum(datumData);
 	}
@@ -737,7 +741,8 @@ CopyStringInfo(StringInfo sourceString)
 		targetString->data = palloc0(sourceString->len);
 		targetString->len = sourceString->len;
 		targetString->maxlen = sourceString->len;
-		memcpy(targetString->data, sourceString->data, sourceString->len);
+		memcpy_s(targetString->data, sourceString->len,
+				 sourceString->data, sourceString->len);
 	}
 
 	return targetString;