diff --git a/server/handler.go b/server/handler.go
index 9a2bf66b1c..3f5d47ac66 100644
--- a/server/handler.go
+++ b/server/handler.go
@@ -15,6 +15,7 @@
 package server
 
 import (
+	goerrors "errors"
 	"io"
 	"net"
 	"regexp"
@@ -23,8 +24,6 @@ import (
 	"sync"
 	"time"
 
-	goerrors "errors"
-
 	"github.com/dolthub/vitess/go/mysql"
 	"github.com/dolthub/vitess/go/netutil"
 	"github.com/dolthub/vitess/go/sqltypes"
diff --git a/sql/mysql_db/mysql_db.go b/sql/mysql_db/mysql_db.go
index db0b7877e7..53aa1f4b54 100644
--- a/sql/mysql_db/mysql_db.go
+++ b/sql/mysql_db/mysql_db.go
@@ -23,6 +23,8 @@ import (
 	"net"
 	"sort"
 	"strings"
+	"sync"
+	"time"
 
 	"github.com/dolthub/vitess/go/mysql"
 	flatbuffers "github.com/google/flatbuffers/go"
@@ -237,6 +239,48 @@ func (db *MySQLDb) AddSuperUser(username string, host string, password string) {
 	db.updateCounter++
 }
 
+type LockUserMap struct {
+	sync.Map
+}
+
+func (m *LockUserMap) SetUser(readUserEntry *User, value time.Time) {
+	m.Set(fmt.Sprintf("%s-%s", readUserEntry.User, readUserEntry.Host), value)
+}
+
+func (m *LockUserMap) Set(key string, value time.Time) {
+	m.Store(key, value)
+}
+
+func (m *LockUserMap) GetUser(readUserEntry *User) (time.Time, bool) {
+	return m.Get(fmt.Sprintf("%s-%s", readUserEntry.User, readUserEntry.Host))
+}
+
+func (m *LockUserMap) Get(key string) (time.Time, bool) {
+	val, ok := m.Load(key)
+	if !ok {
+		return time.Time{}, false
+	}
+	return val.(time.Time), true
+}
+
+func (m *LockUserMap) RemoveUser(readUserEntry *User) {
+	m.Delete(fmt.Sprintf("%s-%s", readUserEntry.User, readUserEntry.Host))
+}
+
+func (m *LockUserMap) Remove(key string) {
+	m.Delete(key)
+}
+
+var lockUserMap = &LockUserMap{}
+
+func (db *MySQLDb) LockUser(readUserEntry *User) {
+	if readUserEntry == nil {
+		return
+	} else {
+		lockUserMap.SetUser(readUserEntry, time.Now())
+	}
+}
+
 // GetUser returns a user matching the given user and host if it exists. Due to the slight difference between users and
 // roles, roleSearch changes whether the search matches against user or role rules.
 func (db *MySQLDb) GetUser(user string, host string, roleSearch bool) *User {
@@ -258,7 +302,31 @@ func (db *MySQLDb) GetUser(user string, host string, roleSearch bool) *User {
 	})
 
 	if len(userEntries) == 1 {
-		return userEntries[0].(*User)
+		readUserEntry := userEntries[0].(*User)
+
+		if lockTime, isLocked := lockUserMap.GetUser(readUserEntry); isLocked {
+			if time.Since(lockTime) > time.Hour {
+				readUserEntry.Locked = false
+				lockUserMap.RemoveUser(readUserEntry)
+			} else {
+				readUserEntry.Locked = true
+				return readUserEntry
+			}
+		}
+		if strings.Contains(readUserEntry.Host, "/") {
+			_, network, cidrParseErr := net.ParseCIDR(readUserEntry.Host)
+			if cidrParseErr == nil {
+				hostIp := net.ParseIP(host)
+				if hostIp != nil && network.Contains(hostIp) {
+					return readUserEntry
+				} else {
+					return nil
+				}
+			} else {
+				return nil
+			}
+		}
+		return readUserEntry
 	}
 
 	// First we check for matches on the same user, then we try the anonymous user
@@ -268,6 +336,16 @@ func (db *MySQLDb) GetUser(user string, host string, roleSearch bool) *User {
 		})
 		for _, readUserEntry := range userEntries {
 			readUserEntry := readUserEntry.(*User)
+
+			if lockTime, isLocked := lockUserMap.GetUser(readUserEntry); isLocked {
+				if time.Since(lockTime) > time.Hour {
+					readUserEntry.Locked = false
+					lockUserMap.RemoveUser(readUserEntry)
+				} else {
+					readUserEntry.Locked = true
+					return readUserEntry
+				}
+			}
 			if strings.Contains(readUserEntry.Host, "/") {
 				_, network, cidrParseErr := net.ParseCIDR(readUserEntry.Host)
 				if cidrParseErr == nil {
@@ -445,6 +523,7 @@ func (db *MySQLDb) ValidateHash(salt []byte, user string, authResponse []byte, a
 	}
 	if len(userEntry.Password) > 0 {
 		if !validateMysqlNativePassword(authResponse, salt, userEntry.Password) {
+			db.LockUser(userEntry)
 			return nil, mysql.NewSQLError(mysql.ERAccessDeniedError, mysql.SSAccessDeniedError, "Access denied for user '%v'", user)
 		}
 	} else if len(authResponse) > 0 { // password is nil or empty, therefore no password is set