diff --git a/TODO.md b/TODO.md
index 398dcd8..b9dbfd7 100644
--- a/TODO.md
+++ b/TODO.md
@@ -41,3 +41,4 @@
 - [x] pdf-viewer: fix toolbar width (align-self:stretch), hide sibling file items when expanded
 - [x] Fix createThesis SQL: extra `?` placeholder in VALUES (27 values for 26 columns) + add integration tests
 - [x] CSV import/export: single source of truth (CSV_COLUMNS), add missing columns (duration, annexes, license_custom, contact_visible, objet, cc2r, exemplaires), fix XamxamInitFilePonds → window.n, generate import hint from headers
+- [x] Extend admin auth cookie lifetime from session-only to 1 week (604800s)
diff --git a/app/src/AdminAuth.php b/app/src/AdminAuth.php
index d699902..2ea380c 100644
--- a/app/src/AdminAuth.php
+++ b/app/src/AdminAuth.php
@@ -30,7 +30,7 @@ class AdminAuth
         }
         // Harden session cookie (item #8)
         session_set_cookie_params([
-            'lifetime' => 0,
+            'lifetime' => 604800,
             'path'     => '/admin',
             'secure'   => (php_sapi_name() !== 'cli-server'),
             'httponly' => true,