diff --git a/src/functions/backend/auth/admin-api-guard.ts b/src/functions/backend/auth/admin-api-guard.ts
new file mode 100644
index 0000000..4b89d49
--- /dev/null
+++ b/src/functions/backend/auth/admin-api-guard.ts
@@ -0,0 +1,37 @@
+import type { APIResponseObject } from "@moduletrace/bunext/types";
+import checkUserAccess from "./check-user-access";
+import userAuth from "./user-auth";
+
+type Params = {
+    req: Request;
+};
+
+/**
+ * Guard for admin API routes. Returns an error
+ * response if the request is not from a logged in
+ * user with admin access, otherwise `undefined`
+ */
+export default async function adminApiGuard({
+    req,
+}: Params): Promise<APIResponseObject | undefined> {
+    const { user, user_types } = await userAuth({ req });
+
+    if (!user?.logged_in_status) {
+        return {
+            success: false,
+            msg: `Unauthorized`,
+            logoutUser: true,
+        };
+    }
+
+    const is_super_admin = checkUserAccess({ user_types });
+
+    if (!is_super_admin.success) {
+        return {
+            success: false,
+            msg: `Unauthorized`,
+        };
+    }
+
+    return undefined;
+}
diff --git a/src/functions/backend/setup/delete-wireguard-host.ts b/src/functions/backend/setup/delete-wireguard-host.ts
index 365d1ed..5dfb4f9 100644
--- a/src/functions/backend/setup/delete-wireguard-host.ts
+++ b/src/functions/backend/setup/delete-wireguard-host.ts
@@ -11,7 +11,7 @@ import grabHostDirnames from "./grab-host-dir-names";
 import grabClientDirnames from "./grab-client-dir-names";
 import removeSubnetFirewallRules from "../firewall/remove-subnet-firewall-rules";
 import { AppData } from "@/src/data/app-data";
-import { execSync } from "node:child_process";
+import { rmSync } from "node:fs";
 
 type Params = {
     host_id: number;
@@ -56,7 +56,7 @@ export default async function deleteWireguardHost({
             });
 
             try {
-                execSync(`rm -rf ${CLIENT_DIR}`, { encoding: "utf-8" });
+                rmSync(CLIENT_DIR, { recursive: true, force: true });
             } catch {}
 
             await BunSQLite.delete<BUN_SQLITE_WGUI_CLIENTS, TableType>({
@@ -112,7 +112,7 @@ export default async function deleteWireguardHost({
         }
 
         try {
-            execSync(`rm -rf ${HOST_CONFIG_DIR}`, { encoding: "utf-8" });
+            rmSync(HOST_CONFIG_DIR, { recursive: true, force: true });
         } catch {}
 
         const del_host = await BunSQLite.sql({
diff --git a/src/functions/backend/setup/get-interface-local-ip.ts b/src/functions/backend/setup/get-interface-local-ip.ts
index a76282f..65d9985 100644
--- a/src/functions/backend/setup/get-interface-local-ip.ts
+++ b/src/functions/backend/setup/get-interface-local-ip.ts
@@ -1,4 +1,5 @@
-import { execSync } from "node:child_process";
+import validateInterfaceName from "@/src/utils/validate-interface-name";
+import { execFileSync } from "node:child_process";
 
 /**
  * Get the local IPv4 address of a specific network interface
@@ -8,10 +9,11 @@ import { execSync } from "node:child_process";
 export default async function getInterfaceLocalIP(
     interface_name: string | null,
 ): Promise<string> {
-    if (!interface_name) return ``;
+    if (!validateInterfaceName({ name: interface_name })) return ``;
     try {
-        const output = execSync(
-            `ip -4 addr show ${interface_name}`,
+        const output = execFileSync(
+            "ip",
+            ["-4", "addr", "show", interface_name as string],
             { encoding: "utf-8" },
         ).trim();
         const match = output.match(
diff --git a/src/functions/backend/setup/grab-host-network-interfaces.ts b/src/functions/backend/setup/grab-host-network-interfaces.ts
index 7c02161..9d141e4 100644
--- a/src/functions/backend/setup/grab-host-network-interfaces.ts
+++ b/src/functions/backend/setup/grab-host-network-interfaces.ts
@@ -1,4 +1,5 @@
 import { execSync } from "node:child_process";
+import { existsSync } from "node:fs";
 import os from "node:os";
 
 const VIRTUAL_INTERFACE_PATTERNS = [
@@ -25,15 +26,7 @@ function isVirtualInterface(name: string): boolean {
 }
 
 function isPhysicalInterface(name: string): boolean {
-    try {
-        const devicePath = `/sys/class/net/${name}/device`;
-        const result = execSync(`test -e ${devicePath} && echo yes || echo no`, {
-            encoding: "utf-8",
-        }).trim();
-        return result === "yes";
-    } catch {
-        return true;
-    }
+    return existsSync(`/sys/class/net/${name}/device`);
 }
 
 /**
diff --git a/src/functions/backend/setup/grab-host-public-ip-address.ts b/src/functions/backend/setup/grab-host-public-ip-address.ts
index 4888254..68c3bdc 100644
--- a/src/functions/backend/setup/grab-host-public-ip-address.ts
+++ b/src/functions/backend/setup/grab-host-public-ip-address.ts
@@ -1,4 +1,5 @@
-import { execSync } from "node:child_process";
+import validateInterfaceName from "@/src/utils/validate-interface-name";
+import { execFileSync, execSync } from "node:child_process";
 
 /**
  * Function to grab the host's public
@@ -9,12 +10,20 @@ export default async function grabHostPublicIPAddress(
     interface_name?: string | null,
 ) {
     try {
-        const curl_cmd = interface_name
-            ? `curl -sS --max-time 15 --interface ${interface_name} https://api.ipify.org`
-            : `curl -sS --max-time 15 https://api.ipify.org`;
-        const public_ip = execSync(curl_cmd, {
-            encoding: "utf-8",
-        })
+        const interface_args = validateInterfaceName({ name: interface_name })
+            ? ["--interface", interface_name as string]
+            : [];
+        const public_ip = execFileSync(
+            "curl",
+            [
+                "-sS",
+                "--max-time",
+                "15",
+                ...interface_args,
+                "https://api.ipify.org",
+            ],
+            { encoding: "utf-8" },
+        )
             .trim();
 
         if (/^\d{1,3}(\.\d{1,3}){3}$/.test(public_ip)) {
diff --git a/src/functions/backend/setup/setup-wireguard-client.ts b/src/functions/backend/setup/setup-wireguard-client.ts
index 0b5c85a..5b86efd 100644
--- a/src/functions/backend/setup/setup-wireguard-client.ts
+++ b/src/functions/backend/setup/setup-wireguard-client.ts
@@ -5,7 +5,11 @@ import type {
 import { AppData } from "@/src/data/app-data";
 import grabDirNames from "@/src/utils/grab-dir-names";
 import { execSync } from "node:child_process";
+import { readFileSync, writeFileSync } from "node:fs";
 import path from "node:path";
+import validateIpv4 from "@/src/utils/validate-ipv4";
+import validateAllowedIps from "@/src/utils/validate-allowed-ips";
+import validateEndpointHost from "@/src/utils/validate-endpoint-host";
 import grabHostPublicIPAddress from "./grab-host-public-ip-address";
 import setupWireguardHost from "./setup-wireguard-host";
 import type { APIResponseObject } from "@moduletrace/bunext/types";
@@ -72,6 +76,24 @@ export default async function setupWireguardClient({
         };
     }
 
+    if (!validateIpv4({ ip: CLIENT_WG_IP })) {
+        return {
+            success: false,
+            msg: `Invalid Client Private IP address: ${CLIENT_WG_IP}`,
+        };
+    }
+
+    if (
+        client?.allow_all_ips != 1 &&
+        client?.allowed_ips &&
+        !validateAllowedIps({ value: client.allowed_ips })
+    ) {
+        return {
+            success: false,
+            msg: `Invalid Allowed IPs: ${client.allowed_ips}`,
+        };
+    }
+
     const HOST_WG_IP = resolved_host?.wg_ip_address;
 
     if (!HOST_WG_IP) {
@@ -104,53 +126,57 @@ export default async function setupWireguardClient({
             client?.public_ip_address ||
             HOST_WG_IP;
 
-        const CLIENT_PRIVATE_KEY = execSync(`cat ${CLIENT_PRIVATE_KEY_FILE}`, {
-            encoding: "utf-8",
-        }).trim();
+        if (!validateEndpointHost({ value: PUBLIC_IP_ADDRESS })) {
+            return {
+                success: false,
+                msg: `Invalid Host public IP address: ${PUBLIC_IP_ADDRESS}`,
+            };
+        }
 
-        const CLIENT_PUBLIC_KEY = execSync(`cat ${CLIENT_PUBLIC_KEY_FILE}`, {
-            encoding: "utf-8",
-        }).trim();
+        const LISTEN_PORT = Number(
+            resolved_host?.listen_port || AppData["DefaultWGListenPort"],
+        );
 
-        const HOST_PUBLIC_KEY = execSync(
-            `cat ${path.join(HOST_CONFIG_DIR, WIREGUARD_PUBLIC_KEY_FILE_NAME)}`,
-            { encoding: "utf-8" },
+        if (!Number.isInteger(LISTEN_PORT)) {
+            return {
+                success: false,
+                msg: `Invalid Host listen port: ${resolved_host?.listen_port}`,
+            };
+        }
+
+        const CLIENT_PRIVATE_KEY = readFileSync(
+            CLIENT_PRIVATE_KEY_FILE,
+            "utf-8",
         ).trim();
 
-        let sh = ``;
+        const HOST_PUBLIC_KEY = readFileSync(
+            path.join(HOST_CONFIG_DIR, WIREGUARD_PUBLIC_KEY_FILE_NAME),
+            "utf-8",
+        ).trim();
 
-        sh += `cd ${CLIENT_DIR}\n`;
-        sh += `cat > ${WIREGUARD_CLIENT_CONFIG_FILE_NAME} << EOF\n`;
-        sh += `\n`;
-        sh += `[Interface]\n`;
-        sh += `Address = ${CLIENT_WG_IP}/32\n`;
-        sh += `PrivateKey = ${CLIENT_PRIVATE_KEY}\n`;
+        let CLIENT_CONFIG = ``;
+
+        CLIENT_CONFIG += `\n`;
+        CLIENT_CONFIG += `[Interface]\n`;
+        CLIENT_CONFIG += `Address = ${CLIENT_WG_IP}/32\n`;
+        CLIENT_CONFIG += `PrivateKey = ${CLIENT_PRIVATE_KEY}\n`;
         if (client?.allow_all_ips == 1) {
-            sh += `DNS = 1.1.1.1\n`;
+            CLIENT_CONFIG += `DNS = 1.1.1.1\n`;
         }
-        sh += `\n`;
-        sh += `[Peer]\n`;
-        sh += `PublicKey = ${HOST_PUBLIC_KEY}\n`;
-        sh += `Endpoint = ${PUBLIC_IP_ADDRESS}:${resolved_host?.listen_port || AppData["DefaultWGListenPort"]}\n`;
+        CLIENT_CONFIG += `\n`;
+        CLIENT_CONFIG += `[Peer]\n`;
+        CLIENT_CONFIG += `PublicKey = ${HOST_PUBLIC_KEY}\n`;
+        CLIENT_CONFIG += `Endpoint = ${PUBLIC_IP_ADDRESS}:${LISTEN_PORT}\n`;
 
         if (client?.allow_all_ips == 1) {
-            sh += `AllowedIPs = 0.0.0.0/0, ::/0\n`;
+            CLIENT_CONFIG += `AllowedIPs = 0.0.0.0/0, ::/0\n`;
         } else if (client?.allowed_ips) {
-            sh += `AllowedIPs = ${client.allowed_ips}\n`;
+            CLIENT_CONFIG += `AllowedIPs = ${client.allowed_ips}\n`;
         }
 
-        sh += `PersistentKeepalive = 25\n`;
+        CLIENT_CONFIG += `PersistentKeepalive = 25\n`;
 
-        sh += `EOF\n`;
-        sh += `\n`;
-
-        const exec = execSync(sh, {
-            encoding: "utf-8",
-        });
-
-        const CLIENT_CONFIG = execSync(`cat ${CLIENT_CONFIG_FILE}`, {
-            encoding: "utf-8",
-        });
+        writeFileSync(CLIENT_CONFIG_FILE, CLIENT_CONFIG, { mode: 0o600 });
 
         const host_setup_res = skip_host_setup
             ? { success: true }
diff --git a/src/functions/backend/setup/setup-wireguard-host.ts b/src/functions/backend/setup/setup-wireguard-host.ts
index ff74ef0..fa0abde 100644
--- a/src/functions/backend/setup/setup-wireguard-host.ts
+++ b/src/functions/backend/setup/setup-wireguard-host.ts
@@ -5,6 +5,8 @@ import type {
 } from "@/db/types/db";
 import grabDirNames from "@/src/utils/grab-dir-names";
 import { execSync } from "node:child_process";
+import { chmodSync, mkdirSync, readFileSync, writeFileSync } from "node:fs";
+import validateIpv4 from "@/src/utils/validate-ipv4";
 import type { APIResponseObject } from "@moduletrace/bunext/types";
 import BunSQLite from "@moduletrace/bun-sqlite";
 import type { TableType, User } from "@/src/types";
@@ -125,6 +127,24 @@ export default async function setupWireguardHost({
         };
     }
 
+    if (!validateIpv4({ ip: HOST_WG_IP })) {
+        return {
+            success: false,
+            msg: `Invalid Host Private IP address: ${HOST_WG_IP}`,
+        };
+    }
+
+    const LISTEN_PORT = Number(
+        host?.listen_port || AppData["DefaultWGListenPort"],
+    );
+
+    if (!Number.isInteger(LISTEN_PORT)) {
+        return {
+            success: false,
+            msg: `Invalid Host listen port: ${host?.listen_port}`,
+        };
+    }
+
     const is_ip_available = is_update_after_client_setup
         ? { success: true }
         : host?.wg_ip_address
@@ -163,13 +183,12 @@ export default async function setupWireguardHost({
     }
 
     try {
-        const HOST_PUBLIC_KEY = execSync(`cat ${HOST_PUBLIC_KEY_FILE}`, {
-            encoding: "utf-8",
-        }).trim();
+        const HOST_PUBLIC_KEY = readFileSync(HOST_PUBLIC_KEY_FILE, "utf-8").trim();
 
-        const HOST_PRIVATE_KEY = execSync(`cat ${HOST_PRIVATE_KEY_FILE}`, {
-            encoding: "utf-8",
-        }).trim();
+        const HOST_PRIVATE_KEY = readFileSync(
+            HOST_PRIVATE_KEY_FILE,
+            "utf-8",
+        ).trim();
 
         if (!is_update_after_client_setup) {
             const update_host = await BunSQLite.insert<
@@ -189,12 +208,6 @@ export default async function setupWireguardHost({
             });
         }
 
-        let sh = ``;
-
-        sh += `set -e\n`;
-
-        sh += `cd ${HOST_CONFIG_DIR}\n`;
-
         const HOST_SUBNET = `${HOST_WG_IP.split(".").slice(0, 3).join(".")}.0/24`;
 
         const iptables_scripts = buildHostIptablesScripts({
@@ -224,53 +237,53 @@ export default async function setupWireguardHost({
             };
         }
 
-        execSync(`mkdir -p ${HOST_IPTABLES_DIR}`, { encoding: "utf-8" });
+        mkdirSync(HOST_IPTABLES_DIR, { recursive: true });
         await Bun.write(POST_UP_PATH, iptables_scripts.post_up);
         await Bun.write(POST_DOWN_PATH, iptables_scripts.post_down);
-        execSync(`chmod +x ${POST_UP_PATH} ${POST_DOWN_PATH}`, {
-            encoding: "utf-8",
-        });
+        chmodSync(POST_UP_PATH, 0o755);
+        chmodSync(POST_DOWN_PATH, 0o755);
 
-        sh += `cat > ${INTERFACE_NAME}.conf << EOF\n`;
-        sh += `[Interface]\n`;
-        sh += `Address = ${HOST_WG_IP}/24\n`;
-        sh += `ListenPort = ${host?.listen_port || AppData["DefaultWGListenPort"]}\n`;
-        sh += `PrivateKey = ${HOST_PRIVATE_KEY}\n`;
-        sh += `PostUp = ${POST_UP_PATH}\n`;
-        sh += `PostDown = ${POST_DOWN_PATH}\n`;
-        sh += `\n`;
+        let HOST_CONFIG = ``;
+
+        HOST_CONFIG += `[Interface]\n`;
+        HOST_CONFIG += `Address = ${HOST_WG_IP}/24\n`;
+        HOST_CONFIG += `ListenPort = ${LISTEN_PORT}\n`;
+        HOST_CONFIG += `PrivateKey = ${HOST_PRIVATE_KEY}\n`;
+        HOST_CONFIG += `PostUp = ${POST_UP_PATH}\n`;
+        HOST_CONFIG += `PostDown = ${POST_DOWN_PATH}\n`;
+        HOST_CONFIG += `\n`;
 
         if (clients[0]) {
             for (let i = 0; i < clients.length; i++) {
                 const client = clients[i];
                 if (!client?.id) continue;
 
+                if (!validateIpv4({ ip: client.wg_ip_address })) {
+                    return {
+                        success: false,
+                        msg: `Invalid Private IP address for client ${client.id}: ${client.wg_ip_address}`,
+                    };
+                }
+
                 const { CLIENT_PUBLIC_KEY_FILE } = grabClientDirnames({
                     client,
                     host_id: HOST_ID,
                 });
 
-                const CLIENT_PUBLIC_KEY = execSync(
-                    `cat ${CLIENT_PUBLIC_KEY_FILE}`,
-                    {
-                        encoding: "utf-8",
-                    },
+                const CLIENT_PUBLIC_KEY = readFileSync(
+                    CLIENT_PUBLIC_KEY_FILE,
+                    "utf-8",
                 ).trim();
 
-                sh += `[Peer]\n`;
-                sh += `PublicKey = ${CLIENT_PUBLIC_KEY}\n`;
-                sh += `AllowedIPs = ${client.wg_ip_address}/32\n`;
-                sh += `\n`;
+                HOST_CONFIG += `[Peer]\n`;
+                HOST_CONFIG += `PublicKey = ${CLIENT_PUBLIC_KEY}\n`;
+                HOST_CONFIG += `AllowedIPs = ${client.wg_ip_address}/32\n`;
+                HOST_CONFIG += `\n`;
             }
         }
 
-        sh += `EOF\n`;
-
-        sh += `chmod 600 ${INTERFACE_NAME}.conf\n`;
-
-        sh += `\n`;
-
-        const exec = execSync(sh, { encoding: "utf-8" });
+        writeFileSync(HOST_CONFIG_FILE, HOST_CONFIG, { mode: 0o600 });
+        chmodSync(HOST_CONFIG_FILE, 0o600);
 
         if (!is_update_after_client_setup) {
             execSync(
@@ -293,7 +306,7 @@ export default async function setupWireguardHost({
 
         const firewall_res = await allowSubnetFirewallRules({
             subnet: HOST_SUBNET,
-            listen_port: host?.listen_port || AppData["DefaultWGListenPort"],
+            listen_port: LISTEN_PORT,
         });
 
         if (!firewall_res.success) {
@@ -304,7 +317,7 @@ export default async function setupWireguardHost({
 
         return {
             success: true,
-            msg: [exec.trim(), manage_res.msg, firewall_res.msg].join("\n\n"),
+            msg: [manage_res.msg, firewall_res.msg].join("\n\n"),
         };
     } catch (error: any) {
         console.log(
diff --git a/src/functions/server/media/handle-media-server.ts b/src/functions/server/media/handle-media-server.ts
index ef283aa..0c3f3f3 100644
--- a/src/functions/server/media/handle-media-server.ts
+++ b/src/functions/server/media/handle-media-server.ts
@@ -65,6 +65,10 @@ export default async function handleMediaServer({
         throw new Error(`Media record not found!`);
     }
 
+    if (privacy != "private" && media.is_private == 1) {
+        throw new Error(`Media record not found!`);
+    }
+
     const media_location = thumbnail
         ? media.media_thumbnail_write_path
         : media.media_write_path;
diff --git a/src/pages/api/admin/crud/(tables)/clients/del.ts b/src/pages/api/admin/crud/(tables)/clients/del.ts
index 7b981d4..b96dc54 100644
--- a/src/pages/api/admin/crud/(tables)/clients/del.ts
+++ b/src/pages/api/admin/crud/(tables)/clients/del.ts
@@ -1,5 +1,5 @@
 import _ from "lodash";
-import { execSync } from "node:child_process";
+import { rmSync } from "node:fs";
 import path from "node:path";
 import type { AdminCrudAPIParams, TableType } from "@/src/types";
 import type { APIResponseObject } from "@moduletrace/bunext/types";
@@ -14,7 +14,7 @@ import type {
     BUN_SQLITE_WGUI_HOSTS,
 } from "@/db/types/db";
 import BunSQLite from "@moduletrace/bun-sqlite";
-import type { ServerQueryParam } from "@moduletrace/bun-sqlite/dist/types";
+import type { ServerQueryParam } from "@moduletrace/bun-sqlite/types";
 import grabClientDirnames from "@/src/functions/backend/setup/grab-client-dir-names";
 
 const { WGUI_LIB_HOSTS_CONFIGS_DIR, WGUI_LIB_HOST_CLIENTS_DIR_NAME } =
@@ -72,7 +72,7 @@ export default async function (
         });
 
         try {
-            execSync(`rm -rf ${CLIENT_DIR}`, { encoding: "utf-8" });
+            rmSync(CLIENT_DIR, { recursive: true, force: true });
         } catch (error) {}
 
         affected_host_ids.add(host_id);
diff --git a/src/pages/api/admin/interface-local-ip.ts b/src/pages/api/admin/interface-local-ip.ts
index e98f1f1..d7cee2a 100644
--- a/src/pages/api/admin/interface-local-ip.ts
+++ b/src/pages/api/admin/interface-local-ip.ts
@@ -1,5 +1,5 @@
 import getInterfaceLocalIP from "@/src/functions/backend/setup/get-interface-local-ip";
-import type { ApiReqParams } from "@/src/types";
+import adminApiGuard from "@/src/functions/backend/auth/admin-api-guard";
 import type {
     APIResponseObject,
     BunextAPIRouteHandler,
@@ -11,6 +11,13 @@ export const handler: BunextAPIRouteHandler<APIResponseObject> = async (
     if (params.req.method !== "GET") {
         return { success: false };
     }
+
+    const unauthorized_res = await adminApiGuard({ req: params.req });
+
+    if (unauthorized_res) {
+        return unauthorized_res;
+    }
+
     const url = new URL(params.req.url || "");
     const iface = url.searchParams.get("interface") || undefined;
     try {
diff --git a/src/pages/api/admin/network-interfaces.ts b/src/pages/api/admin/network-interfaces.ts
index 4495a26..014fa30 100644
--- a/src/pages/api/admin/network-interfaces.ts
+++ b/src/pages/api/admin/network-interfaces.ts
@@ -1,5 +1,5 @@
 import grabHostNetworkInterfaces from "@/src/functions/backend/setup/grab-host-network-interfaces";
-import type { ApiReqParams } from "@/src/types";
+import adminApiGuard from "@/src/functions/backend/auth/admin-api-guard";
 import type {
     APIResponseObject,
     BunextAPIRouteHandler,
@@ -11,6 +11,13 @@ export const handler: BunextAPIRouteHandler<APIResponseObject> = async (
     if (params.req.method !== "GET") {
         return { success: false };
     }
+
+    const unauthorized_res = await adminApiGuard({ req: params.req });
+
+    if (unauthorized_res) {
+        return unauthorized_res;
+    }
+
     try {
         const interfaces = await grabHostNetworkInterfaces();
         return { success: true, stringRes: JSON.stringify(interfaces) };
diff --git a/src/pages/api/admin/next-listen-port.ts b/src/pages/api/admin/next-listen-port.ts
index 83c42e2..7d57f4d 100644
--- a/src/pages/api/admin/next-listen-port.ts
+++ b/src/pages/api/admin/next-listen-port.ts
@@ -1,5 +1,5 @@
 import getNextAvailableListenPort from "@/src/functions/backend/setup/get-next-available-listen-port";
-import type { ApiReqParams } from "@/src/types";
+import adminApiGuard from "@/src/functions/backend/auth/admin-api-guard";
 import type {
     APIResponseObject,
     BunextAPIRouteHandler,
@@ -11,6 +11,13 @@ export const handler: BunextAPIRouteHandler<APIResponseObject> = async (
     if (params.req.method !== "GET") {
         return { success: false };
     }
+
+    const unauthorized_res = await adminApiGuard({ req: params.req });
+
+    if (unauthorized_res) {
+        return unauthorized_res;
+    }
+
     try {
         const port = await getNextAvailableListenPort();
         return { success: true, numberRes: port };
diff --git a/src/pages/api/admin/public-ip.ts b/src/pages/api/admin/public-ip.ts
index edb4605..6ae8486 100644
--- a/src/pages/api/admin/public-ip.ts
+++ b/src/pages/api/admin/public-ip.ts
@@ -1,5 +1,5 @@
 import grabHostPublicIPAddress from "@/src/functions/backend/setup/grab-host-public-ip-address";
-import type { ApiReqParams } from "@/src/types";
+import adminApiGuard from "@/src/functions/backend/auth/admin-api-guard";
 import type {
     APIResponseObject,
     BunextAPIRouteHandler,
@@ -11,6 +11,13 @@ export const handler: BunextAPIRouteHandler<APIResponseObject> = async (
     if (params.req.method !== "GET") {
         return { success: false };
     }
+
+    const unauthorized_res = await adminApiGuard({ req: params.req });
+
+    if (unauthorized_res) {
+        return unauthorized_res;
+    }
+
     const url = new URL(params.req.url || "");
     const iface = url.searchParams.get("interface") || undefined;
     try {
diff --git a/src/utils/validate-allowed-ips.test.ts b/src/utils/validate-allowed-ips.test.ts
new file mode 100644
index 0000000..b7c6372
--- /dev/null
+++ b/src/utils/validate-allowed-ips.test.ts
@@ -0,0 +1,16 @@
+import { describe, expect, test } from "bun:test";
+import validateAllowedIps from "./validate-allowed-ips";
+
+describe("validateAllowedIps", () => {
+    test("accepts single and comma-separated CIDRs", () => {
+        expect(validateAllowedIps({ value: "10.0.0.0/24" })).toBe(true);
+        expect(validateAllowedIps({ value: "10.0.0.0/24, 192.168.1.5/32" })).toBe(true);
+    });
+
+    test("rejects empty and unsafe values", () => {
+        expect(validateAllowedIps({ value: "" })).toBe(false);
+        expect(validateAllowedIps({ value: "$(id)" })).toBe(false);
+        expect(validateAllowedIps({ value: "10.0.0.0/24\nPostUp = id" })).toBe(false);
+        expect(validateAllowedIps({ value: "10.0.0.0/24," })).toBe(false);
+    });
+});
diff --git a/src/utils/validate-allowed-ips.ts b/src/utils/validate-allowed-ips.ts
new file mode 100644
index 0000000..e099628
--- /dev/null
+++ b/src/utils/validate-allowed-ips.ts
@@ -0,0 +1,19 @@
+import validateIpv4Cidr from "./validate-ipv4-cidr";
+
+type Params = {
+    value?: string | null;
+};
+
+/**
+ * Validate a comma-separated list of IPv4
+ * addresses/CIDRs (WireGuard `AllowedIPs`)
+ */
+export default function validateAllowedIps({ value }: Params) {
+    if (!value) {
+        return false;
+    }
+
+    return value
+        .split(",")
+        .every((entry) => validateIpv4Cidr({ value: entry.trim() }));
+}
diff --git a/src/utils/validate-endpoint-host.test.ts b/src/utils/validate-endpoint-host.test.ts
new file mode 100644
index 0000000..ecad9bc
--- /dev/null
+++ b/src/utils/validate-endpoint-host.test.ts
@@ -0,0 +1,15 @@
+import { describe, expect, test } from "bun:test";
+import validateEndpointHost from "./validate-endpoint-host";
+
+describe("validateEndpointHost", () => {
+    test("accepts IPv4 addresses and hostnames", () => {
+        expect(validateEndpointHost({ value: "203.0.113.4" })).toBe(true);
+        expect(validateEndpointHost({ value: "vpn.example.com" })).toBe(true);
+    });
+
+    test("rejects empty and unsafe values", () => {
+        expect(validateEndpointHost({ value: "" })).toBe(false);
+        expect(validateEndpointHost({ value: "1.2.3.4\nPostUp = id" })).toBe(false);
+        expect(validateEndpointHost({ value: "$(id)" })).toBe(false);
+    });
+});
diff --git a/src/utils/validate-endpoint-host.ts b/src/utils/validate-endpoint-host.ts
new file mode 100644
index 0000000..bdc1f9a
--- /dev/null
+++ b/src/utils/validate-endpoint-host.ts
@@ -0,0 +1,23 @@
+import validateIpv4 from "./validate-ipv4";
+
+type Params = {
+    value?: string | null;
+};
+
+/**
+ * Validate a WireGuard `Endpoint` host: an IPv4
+ * address or a DNS hostname
+ */
+export default function validateEndpointHost({ value }: Params) {
+    if (!value) {
+        return false;
+    }
+
+    if (validateIpv4({ ip: value })) {
+        return true;
+    }
+
+    return /^(?=.{1,253}$)[A-Za-z0-9](?:[A-Za-z0-9-]{0,61}[A-Za-z0-9])?(?:\.[A-Za-z0-9](?:[A-Za-z0-9-]{0,61}[A-Za-z0-9])?)*$/.test(
+        value,
+    );
+}
diff --git a/src/utils/validate-interface-name.test.ts b/src/utils/validate-interface-name.test.ts
new file mode 100644
index 0000000..db69198
--- /dev/null
+++ b/src/utils/validate-interface-name.test.ts
@@ -0,0 +1,20 @@
+import { describe, expect, test } from "bun:test";
+import validateInterfaceName from "./validate-interface-name";
+
+describe("validateInterfaceName", () => {
+    test("accepts common interface names", () => {
+        expect(validateInterfaceName({ name: "eth0" })).toBe(true);
+        expect(validateInterfaceName({ name: "enp2s0" })).toBe(true);
+        expect(validateInterfaceName({ name: "wgui1" })).toBe(true);
+        expect(validateInterfaceName({ name: "eth0.100" })).toBe(true);
+    });
+
+    test("rejects empty, long, and shell-unsafe names", () => {
+        expect(validateInterfaceName({ name: "" })).toBe(false);
+        expect(validateInterfaceName({ name: null })).toBe(false);
+        expect(validateInterfaceName({ name: "a".repeat(16) })).toBe(false);
+        expect(validateInterfaceName({ name: "lo;id" })).toBe(false);
+        expect(validateInterfaceName({ name: "lo $(id)" })).toBe(false);
+        expect(validateInterfaceName({ name: "../x" })).toBe(false);
+    });
+});
diff --git a/src/utils/validate-interface-name.ts b/src/utils/validate-interface-name.ts
new file mode 100644
index 0000000..1ae0790
--- /dev/null
+++ b/src/utils/validate-interface-name.ts
@@ -0,0 +1,15 @@
+type Params = {
+    name?: string | null;
+};
+
+/**
+ * Validate a Linux network interface name
+ * (max 15 chars, no whitespace or shell characters)
+ */
+export default function validateInterfaceName({ name }: Params) {
+    if (!name) {
+        return false;
+    }
+
+    return /^[A-Za-z0-9_.:-]{1,15}$/.test(name);
+}