1 files changed, 4 insertions, 1 deletions

diff --git a/server/middlewares/validators/config.ts b/server/middlewares/validators/config.ts
index d015fa6fe..31b131914 100644
--- a/server/middlewares/validators/config.ts
+++ b/server/middlewares/validators/config.ts
@@ -1,10 +1,11 @@
 import * as express from 'express'
 import { body } from 'express-validator/check'
-import { isUserNSFWPolicyValid, isUserVideoQuotaValid, isUserVideoQuotaDailyValid } from '../../helpers/custom-validators/users'
+import { isUserNSFWPolicyValid, isUserVideoQuotaDailyValid, isUserVideoQuotaValid } from '../../helpers/custom-validators/users'
 import { logger } from '../../helpers/logger'
 import { CustomConfig } from '../../../shared/models/server/custom-config.model'
 import { Emailer } from '../../lib/emailer'
 import { areValidationErrors } from './utils'
+import { isThemeValid } from '../../helpers/custom-validators/plugins'
 
 const customConfigUpdateValidator = [
   body('instance.name').exists().withMessage('Should have a valid instance name'),
@@ -47,6 +48,8 @@ const customConfigUpdateValidator = [
   body('followers.instance.enabled').isBoolean().withMessage('Should have a valid followers of instance boolean'),
   body('followers.instance.manualApproval').isBoolean().withMessage('Should have a valid manual approval boolean'),
 
+  body('theme.default').custom(isThemeValid).withMessage('Should have a valid theme'),
+
   async (req: express.Request, res: express.Response, next: express.NextFunction) => {
     logger.debug('Checking customConfigUpdateValidator parameters', { parameters: req.body })