diff --git a/site-modules/profile/manifests/swh/apt_config.pp b/site-modules/profile/manifests/swh/apt_config.pp
--- a/site-modules/profile/manifests/swh/apt_config.pp
+++ b/site-modules/profile/manifests/swh/apt_config.pp
@@ -42,9 +42,20 @@
       repos    => $repos,
     }
 
+    case $::lsbdistcodename {
+      'buster': {
+        $security_release = "${::lsbdistcodename}/updates"
+      }
+      'bullseye': {
+        $security_release = "${::lsbdistcodename}-security"
+      }
+      default: {
+        fail("Unsupported debian version ${::lsbdistcodename}")
+      }
+    }
     ::apt::source {'debian-security':
       location => $debian_security_mirror,
-      release  => "${::lsbdistcodename}/updates",
+      release  => $security_release,
       repos    => $repos,
     }