diff --git a/plinth/__main__.py b/plinth/__main__.py
index c97ba4d37..8fb8c3d3a 100644
--- a/plinth/__main__.py
+++ b/plinth/__main__.py
@@ -244,6 +244,7 @@ def configure_django():
         CACHES={'default':
                 {'BACKEND': 'django.core.cache.backends.dummy.DummyCache'}},
         CAPTCHA_FONT_PATH=['/usr/share/fonts/truetype/ttf-bitstream-vera/Vera.ttf'],
+        CAPTCHA_LENGTH=6,
         DATABASES={'default':
                    {'ENGINE': 'django.db.backends.sqlite3',
                     'NAME': cfg.store_file}},
diff --git a/plinth/modules/sso/views.py b/plinth/modules/sso/views.py
index 57ecba6fb..c9615c289 100644
--- a/plinth/modules/sso/views.py
+++ b/plinth/modules/sso/views.py
@@ -62,7 +62,8 @@ class SSOLoginView(LoginView):
             if request.user.is_authenticated:
                 return set_ticket_cookie(request.user, response)
             else: # Redirect user to captcha page
-                return HttpResponseRedirect('captcha')
+                redirect = '' if request.path.rstrip('/').endswith('captcha') else 'captcha'
+                return HttpResponseRedirect(redirect)
         return response