diff --git a/access.lua b/access.lua
index 894b32d..306d0bb 100644
--- a/access.lua
+++ b/access.lua
@@ -31,7 +31,7 @@ function cached_jwt_verify(data, secret)
     if res == nil then
         logger:debug("Result not found in cache, checking login")
         -- Perform expensive calculation
-        decoded, err = jwt.verify(data, "HS256", cookie_secret)
+        decoded, err = jwt.verify(data, "HS256", COOKIE_SECRET)
         if not decoded then
             logger:error(err)
             return nil, nil, nil, nil, err
@@ -102,11 +102,11 @@ function check_authentication()
     -- cf. src/authenticators/ldap_ynhuser.py in YunoHost to see how the cookie is actually created
 
     local cookie = ngx.var["cookie_" .. conf["cookie_name"]]
-    if cookie == nil or cookie_secret == nil then
+    if cookie == nil or COOKIE_SECRET == nil then
         return false, nil, nil
     end
 
-    session_id, host, user, pwd, err = cached_jwt_verify(cookie, cookie_secret)
+    session_id, host, user, pwd, err = cached_jwt_verify(cookie, COOKIE_SECRET)
 
     if err ~= nil then
         return false, nil, nil
@@ -296,7 +296,7 @@ function set_basic_auth_header()
         local password_enc_b64, iv_b64 = authPasswordEnc:match("([^|]+)|([^|]+)")
         local password_enc = ngx.decode_base64(password_enc_b64)
         local iv = ngx.decode_base64(iv_b64)
-        password = cipher.new('aes-256-cbc'):decrypt(cookie_secret, iv):final(password_enc)
+        password = cipher.new('aes-256-cbc'):decrypt(COOKIE_SECRET, iv):final(password_enc)
     end
 
     -- Set `Authorization` header to enable HTTP authentification
diff --git a/init.lua b/init.lua
index 06a47f8..561f3bf 100644
--- a/init.lua
+++ b/init.lua
@@ -19,7 +19,7 @@ package.path = package.path .. ";"..script_path.."?.lua"
 -- add www-data in the file permissions, which could otherwise lead
 -- to comprised apps running with the www-data group to read the secret file?
 local config = require("config")
-cookie_secret = config.get_cookie_secret()
+COOKIE_SECRET = config.get_cookie_secret()
 
 --
 -- Init logger