diff --git a/monitor/commands/exec.go b/monitor/commands/exec.go
index 1b9dd4db..7a0abe28 100644
--- a/monitor/commands/exec.go
+++ b/monitor/commands/exec.go
@@ -35,6 +35,9 @@ COMMAND and ARG... will be executed in the container.
 }
 
 func (cm *ExecCmd) Exec(ctx context.Context, args []string) error {
+	if ref := cm.m.AttachedSessionID(); ref == "" {
+		return errors.Errorf("no attaching session")
+	}
 	if len(args) < 2 {
 		return errors.Errorf("command must be passed")
 	}
diff --git a/monitor/commands/rollback.go b/monitor/commands/rollback.go
index 0ac986a4..d56e4161 100644
--- a/monitor/commands/rollback.go
+++ b/monitor/commands/rollback.go
@@ -7,6 +7,7 @@ import (
 
 	controllerapi "github.com/docker/buildx/controller/pb"
 	"github.com/docker/buildx/monitor/types"
+	"github.com/pkg/errors"
 )
 
 type RollbackCmd struct {
@@ -37,6 +38,9 @@ COMMAND and ARG... will be executed in the container.
 }
 
 func (cm *RollbackCmd) Exec(ctx context.Context, args []string) error {
+	if ref := cm.m.AttachedSessionID(); ref == "" {
+		return errors.Errorf("no attaching session")
+	}
 	cfg := cm.invokeConfig
 	if len(args) >= 2 {
 		cmds := args[1:]