From e23c69f953974a5853b6f11054a80cf2c4e9510f Mon Sep 17 00:00:00 2001
From: Dan Lock <codenil@proton.me>
Date: Tue, 17 Feb 2026 16:20:16 +0000
Subject: [PATCH] nixos/radarr: harden systemd services

---
 .../modules/services/misc/servarr/radarr.nix  | 34 +++++++++++++++++++
 1 file changed, 34 insertions(+)

diff --git a/nixos/modules/services/misc/servarr/radarr.nix b/nixos/modules/services/misc/servarr/radarr.nix
index 9ca4b889de63..8619790dbcfe 100644
--- a/nixos/modules/services/misc/servarr/radarr.nix
+++ b/nixos/modules/services/misc/servarr/radarr.nix
@@ -64,6 +64,40 @@ in
         EnvironmentFile = cfg.environmentFiles;
         ExecStart = "${cfg.package}/bin/Radarr -nobrowser -data='${cfg.dataDir}'";
         Restart = "on-failure";
+
+        # Hardening
+        CapabilityBoundingSet = "";
+        NoNewPrivileges = true;
+        ProtectHome = true;
+        ProtectClock = true;
+        ProtectKernelLogs = true;
+        PrivateTmp = true;
+        PrivateDevices = true;
+        PrivateUsers = true;
+        ProtectKernelTunables = true;
+        ProtectKernelModules = true;
+        ProtectControlGroups = true;
+        RestrictSUIDSGID = true;
+        RemoveIPC = true;
+        UMask = "0022";
+        ProtectHostname = true;
+        ProtectProc = "invisible";
+        RestrictAddressFamilies = [
+          "AF_INET"
+          "AF_INET6"
+          "AF_UNIX"
+        ];
+        RestrictNamespaces = true;
+        RestrictRealtime = true;
+        LockPersonality = true;
+        SystemCallArchitectures = "native";
+        SystemCallFilter = [
+          "@system-service"
+          "~@privileged"
+          "~@debug"
+          "~@mount"
+          "@chown"
+        ];
       };
     };