diff --git a/peertube-plugin-auth-ldap/main.js b/peertube-plugin-auth-ldap/main.js
index 4f554d6..6854b93 100644
--- a/peertube-plugin-auth-ldap/main.js
+++ b/peertube-plugin-auth-ldap/main.js
@@ -170,8 +170,11 @@ async function login (peertubeHelpers, settingsManager, options) {
         return res(null)
       }
 
+      let username = user[usernameProperty] || ''
+      username = username.replace(/[^a-z0-9._]/g, '_')
+
       return res({
-        username: user[usernameProperty],
+        username,
         email: user[mailProperty]
       })
     })
diff --git a/peertube-plugin-auth-ldap/package.json b/peertube-plugin-auth-ldap/package.json
index 185da2d..db69d81 100644
--- a/peertube-plugin-auth-ldap/package.json
+++ b/peertube-plugin-auth-ldap/package.json
@@ -1,6 +1,6 @@
 {
   "name": "peertube-plugin-auth-ldap",
-  "version": "0.0.3",
+  "version": "0.0.4",
   "description": "Add LDAP support to login form in PeerTube.",
   "engine": {
     "peertube": ">=2.2.0"