diff --git a/sdk/physical/error.go b/sdk/physical/error.go
index d4c6f80e11..8091f178bc 100644
--- a/sdk/physical/error.go
+++ b/sdk/physical/error.go
@@ -4,6 +4,7 @@ import (
 	"context"
 	"errors"
 	"math/rand"
+	"sync"
 	"time"
 
 	log "github.com/hashicorp/go-hclog"
@@ -18,6 +19,7 @@ const (
 type ErrorInjector struct {
 	backend      Backend
 	errorPercent int
+	randomLock   *sync.Mutex
 	random       *rand.Rand
 }
 
@@ -42,6 +44,7 @@ func NewErrorInjector(b Backend, errorPercent int, logger log.Logger) *ErrorInje
 	return &ErrorInjector{
 		backend:      b,
 		errorPercent: errorPercent,
+		randomLock:   new(sync.Mutex),
 		random:       rand.New(rand.NewSource(int64(time.Now().Nanosecond()))),
 	}
 }
@@ -59,7 +62,9 @@ func (e *ErrorInjector) SetErrorPercentage(p int) {
 }
 
 func (e *ErrorInjector) addError() error {
+	e.randomLock.Lock()
 	roll := e.random.Intn(100)
+	e.randomLock.Unlock()
 	if roll < e.errorPercent {
 		return errors.New("random error")
 	}
diff --git a/sdk/physical/latency.go b/sdk/physical/latency.go
index 9304922049..51bb560c2f 100644
--- a/sdk/physical/latency.go
+++ b/sdk/physical/latency.go
@@ -3,6 +3,7 @@ package physical
 import (
 	"context"
 	"math/rand"
+	"sync"
 	"time"
 
 	log "github.com/hashicorp/go-hclog"
@@ -19,6 +20,7 @@ type LatencyInjector struct {
 	backend       Backend
 	latency       time.Duration
 	jitterPercent int
+	randomLock    *sync.Mutex
 	random        *rand.Rand
 }
 
@@ -45,6 +47,7 @@ func NewLatencyInjector(b Backend, latency time.Duration, jitter int, logger log
 		backend:       b,
 		latency:       latency,
 		jitterPercent: jitter,
+		randomLock:    new(sync.Mutex),
 		random:        rand.New(rand.NewSource(int64(time.Now().Nanosecond()))),
 	}
 }
@@ -68,7 +71,9 @@ func (l *LatencyInjector) addLatency() {
 	if l.jitterPercent > 0 {
 		min := 100 - l.jitterPercent
 		max := 100 + l.jitterPercent
+		l.randomLock.Lock()
 		percent = l.random.Intn(max-min) + min
+		l.randomLock.Unlock()
 	}
 	latencyDuration := time.Duration(int(l.latency) * percent / 100)
 	time.Sleep(latencyDuration)