diff --git a/pica-mattermost/Dockerfile b/pica-mattermost/Dockerfile
index 4f87f6b0b0fdc913ead66ee52c76fb5cf3d1c062..2e6507d3f579db0120ab69416d0228709dd9f67b 100644
--- a/pica-mattermost/Dockerfile
+++ b/pica-mattermost/Dockerfile
@@ -13,6 +13,7 @@ ARG PGID=5000
 RUN apk add --no-cache \
 	ca-certificates \
 	curl \
+	jq \
 	libc6-compat \
 	libffi-dev \
   libcap \
diff --git a/pica-mattermost/README.md b/pica-mattermost/README.md
index cbc62d19f0ef23d81d01a549722caffb9587def6..210c1dbf209b2de227c37f02c53453ce63769298 100644
--- a/pica-mattermost/README.md
+++ b/pica-mattermost/README.md
@@ -13,16 +13,16 @@ Aussi, on n'utilise pas le système de sauvegarde `WAL-e`, ce qui nous permet d'
 
 Enfin, le Docker Compose est adapté à notre configuration.
 
-### Utilisation
+### Création d'une nouvelle instance
 
-Assurez-vous que les volumes suivants existent (`docker volume`). Sinon, créez-les avec `docker volume create`.
-* mattermost-config
-* mattermost-db
-* mattermost-data
-* mattermost-plugins
+Assurez-vous que les volumes suivants existent (`docker volume ls`). Sinon, créez-les avec `docker volume create`.
+* `mattermost-config`
+* `mattermost-db`
+* `mattermost-data`
+* `mattermost-plugins`
 
-qduchemi@pica01-test:~/dockerfiles/pica-mattermost$ docker volume create mattermost-plugins
 Copier `secrets/mattermost-db.secrets.example` dans `secrets/mattermost-db.secrets` et remplacer les valeurs des identifiants.
+
 Lancer `docker-compose up -d`. On notera l'utilisation de la variable `DB_HOST` dans le fichier Docker Compose, qui ne devrait pas avoir à être modifiée si on ne touche pas le nom du service de base de données.
 
 ### Procédure de mise à jour
diff --git a/pica-mattermost/clair-whitelist.yml b/pica-mattermost/clair-whitelist.yml
index e69de29bb2d1d6434b8b29ae775ad8c2e48c5391..519b80a6902a5d1ace39d4a9a4ec35524560f5b6 100644
--- a/pica-mattermost/clair-whitelist.yml
+++ b/pica-mattermost/clair-whitelist.yml
@@ -0,0 +1,2 @@
+generalwhitelist:
+  CVE-2016-4074: jq -> pas de contre mesure, pas utilisé par Mattermost mais juste par l'entrypoint, pas de risque en remote
diff --git a/pica-mattermost/entrypoint.sh b/pica-mattermost/entrypoint.sh
index 7d14b1831a7c0679caa7a04f25e04ee56212bacf..437e24ae00922d4a6c2a26d27f89490339c0cbf6 100644
--- a/pica-mattermost/entrypoint.sh
+++ b/pica-mattermost/entrypoint.sh
@@ -11,11 +11,49 @@ if [ "${1:0:1}" = '-' ]; then
 fi
 
 if [ "$1" = 'mattermost' ]; then
+  # Check CLI args for a -config option
+ for ARG in $@;
+ do
+     case "$ARG" in
+         -config=*)
+             MM_CONFIG=${ARG#*=};;
+     esac
+ done
+
+  if [ ! -f $MM_CONFIG ]
+  then
+    # If there is no configuration file, create it with some default values
+    echo "No configuration file" $MM_CONFIG
+    echo "Creating a new one"
+    # Copy default configuration file
+    cp /config.json.save $MM_CONFIG
+    # Substitue some parameters with jq
+    jq '.ServiceSettings.ListenAddress = ":8000"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.LogSettings.EnableConsole = true' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.LogSettings.ConsoleLevel = "ERROR"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.FileSettings.Directory = "/mattermost/data/"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.FileSettings.EnablePublicLink = true' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.FileSettings.PublicLinkSalt = "'$(generate_salt)'"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.EmailSettings.SendEmailNotifications = false' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.EmailSettings.FeedbackEmail = ""' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.EmailSettings.SMTPServer = ""' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.EmailSettings.SMTPPort = ""' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.EmailSettings.InviteSalt = "'$(generate_salt)'"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.EmailSettings.PasswordResetSalt = "'$(generate_salt)'"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.RateLimitSettings.Enable = true' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.SqlSettings.DriverName = "postgres"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.SqlSettings.AtRestEncryptKey = "'$(generate_salt)'"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+    jq '.PluginSettings.Directory = "/mattermost/plugins/"' $MM_CONFIG > $MM_CONFIG.tmp && mv $MM_CONFIG.tmp $MM_CONFIG
+  else
+    echo "Using existing config file" $MM_CONFIG
+  fi
+
   # Configure database access
   if [[ -z "$MM_SQLSETTINGS_DATASOURCE" && ! -z "$MM_USERNAME" && ! -z "$MM_PASSWORD" ]]
   then
-    echo -ne "Configure database connection..."
-    export MM_SQLSETTINGS_DATASOURCE="postgres://$MM_USERNAME:$MM_PASSWORD@$DB_HOST:$DB_PORT_NUMBER/$MM_DBNAME?sslmode=disable&connect_timeout=10"
+    # URLEncode the password, allowing for special characters
+    ENCODED_PASSWORD=$(printf %s $MM_PASSWORD | jq -s -R -r @uri)
+    export MM_SQLSETTINGS_DATASOURCE="postgres://$MM_USERNAME:$ENCODED_PASSWORD@$DB_HOST:$DB_PORT_NUMBER/$MM_DBNAME?sslmode=disable&connect_timeout=10"
     echo OK
   else
     echo "Using existing database connection"