diff --git a/app/admin/service/sys_api.go b/app/admin/service/sys_api.go
index b9bbdfec..fbfc4710 100644
--- a/app/admin/service/sys_api.go
+++ b/app/admin/service/sys_api.go
@@ -6,6 +6,8 @@ import (
 
 	"github.com/go-admin-team/go-admin-core/v2/sdk/runtime"
 	"github.com/go-admin-team/go-admin-core/v2/sdk/service"
+	"gorm.io/gorm"
+
 	"go-admin/app/admin/models"
 	"go-admin/app/admin/service/dto"
 	"go-admin/common/actions"
@@ -78,12 +80,15 @@ func (e *SysApi) Update(c *dto.SysApiUpdateReq, p *actions.DataPermission) error
 		actions.Permission(model.TableName(), p),
 	).First(&model, c.GetId())
 	if err := db.Error; err != nil {
+		// First reports a row the data permission excluded exactly as it
+		// reports one that does not exist, and the caller should not be able
+		// to tell those apart either.
+		if errors.Is(err, gorm.ErrRecordNotFound) {
+			return errors.New("无权更新该数据")
+		}
 		e.Log.Errorf("Service UpdateSysApi error:%s", err)
 		return err
 	}
-	if db.RowsAffected == 0 {
-		return errors.New("无权更新该数据")
-	}
 	c.Generate(&model)
 	db = e.Orm.Save(&model)
 	if err := db.Error; err != nil {
diff --git a/app/admin/service/sys_api_permission_test.go b/app/admin/service/sys_api_permission_test.go
new file mode 100644
index 00000000..11c4e85c
--- /dev/null
+++ b/app/admin/service/sys_api_permission_test.go
@@ -0,0 +1,70 @@
+package service
+
+import (
+	"strings"
+	"testing"
+
+	"github.com/glebarez/sqlite"
+	"github.com/go-admin-team/go-admin-core/v2/logger"
+	"github.com/go-admin-team/go-admin-core/v2/sdk/config"
+	"github.com/go-admin-team/go-admin-core/v2/sdk/service"
+	"gorm.io/gorm"
+
+	"go-admin/app/admin/models"
+	"go-admin/app/admin/service/dto"
+	"go-admin/common/actions"
+)
+
+// An update the data permission excludes has to be refused, and refused in a
+// way that does not tell the caller whether the row exists. First reports both
+// cases the same way - no rows - so the message has to come from there rather
+// than from a RowsAffected check the error return has already skipped past.
+func TestSysApiUpdateRefusesARowOutsideTheDataPermission(t *testing.T) {
+	db, err := gorm.Open(sqlite.Open("file:sysapi-perm?mode=memory&cache=shared"), &gorm.Config{})
+	if err != nil {
+		t.Skipf("sqlite unavailable: %v", err)
+	}
+	if err := db.AutoMigrate(&models.SysApi{}); err != nil {
+		t.Skipf("automigrate: %v", err)
+	}
+
+	prev := config.ApplicationConfig.EnableDP
+	config.ApplicationConfig.EnableDP = true
+	t.Cleanup(func() { config.ApplicationConfig.EnableDP = prev })
+
+	// Owned by user 1.
+	row := models.SysApi{Handle: "h", Title: "t", Path: "/api/v1/probe", Type: "BUS", Action: "GET"}
+	row.CreateBy = 1
+	if err := db.Create(&row).Error; err != nil {
+		t.Fatal(err)
+	}
+
+	e := &SysApi{Service: service.Service{Orm: db, Log: logger.NewHelper(logger.DefaultLogger)}}
+	req := &dto.SysApiUpdateReq{Id: row.Id, Title: "changed"}
+
+	// User 2, scope 5: only rows they created.
+	outsider := &actions.DataPermission{DataScope: "5", UserId: 2, DeptId: 1, RoleId: 2}
+	err = e.Update(req, outsider)
+	if err == nil {
+		t.Fatal("the update was allowed on a row the data permission excludes")
+	}
+	if !strings.Contains(err.Error(), "无权更新该数据") {
+		t.Errorf("refused with %q, want the permission message; a raw database error tells the "+
+			"caller the row exists", err)
+	}
+
+	var after models.SysApi
+	if err := db.First(&after, row.Id).Error; err != nil {
+		t.Fatal(err)
+	}
+	if after.Title != "t" {
+		t.Errorf("the row was modified: title is now %q", after.Title)
+	}
+
+	// The owner still gets through, so the scope is refusing rather than
+	// everything failing.
+	owner := &actions.DataPermission{DataScope: "5", UserId: 1, DeptId: 1, RoleId: 1}
+	if err := e.Update(&dto.SysApiUpdateReq{Id: row.Id, Title: "by owner"}, owner); err != nil {
+		t.Fatalf("the owner could not update their own row: %v", err)
+	}
+}