# Sidebar Login <= 3.0.1 - Authenticated (Subscriber+) Arbitrary Shortcode Execution via Profile Display Name

- **ID:** WPSEC-2026-0845
- **Plugin:** Sidebar Login (`sidebar-login`), https://wordpress.org/plugins/sidebar-login/
- **Affected versions:** all versions before 3.1.0
- **Fixed in:** 3.1.0 (Update to 3.1.0 or later.)
- **Severity:** Medium 5.4 (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N)
- **Weakness:** CWE-94
- **Usage among sites WPSec scans:** plugin Medium, affected versions Medium (as of 2026-10-13)
- **Attack surface analysis:** https://attacksurface.wpsec.com/plugin/sidebar-login
- **Fix released:** 2026-10-12
- **Published:** 2026-10-13
- **URL:** https://wpsec.com/vuln/WPSEC-2026-0845/

## Description

The Sidebar Login plugin for WordPress is vulnerable to arbitrary shortcode execution via profile fields shown in the widget title in all versions up to, and including, 3.0.1. This is due to the plugin substituting user-controlled profile values, such as the display name, first name and last name, into the widget title via template tags (including the default 'Welcome %username%' logged-in title) and then passing the result through do_shortcode() without neutralizing shortcode brackets. This makes it possible for authenticated attackers, with Subscriber-level access and above, to execute arbitrary shortcodes by placing them in their profile name and viewing a page that displays the widget.

## References

- https://wpsec.com/vuln/WPSEC-2026-0845/
- https://plugins.svn.wordpress.org/sidebar-login/tags/3.1.0/
- https://wordpress.org/plugins/sidebar-login/

Source: WPSec, https://wpsec.com/vuln/WPSEC-2026-0845/

License: CC BY 4.0 (https://creativecommons.org/licenses/by/4.0/). Free to use, share and adapt, also commercially, if you credit WPSec and link to this advisory.