CVE-2025-54411 Discourse welcome banner user name XSS
An XSS vulnerability in the Discourse welcome banner allows attackers to execute scripts, potentially compromising user accounts or admin sessions.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- A user has to click or open something
- Fix
- Available
What is CVE-2025-54411?
CVE-2025-54411 is a low-severity cross-site scripting vulnerability in Discourse Discourse, published on 19 Aug 2025. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Official description
Discourse is an open-source discussion platform. Welcome banner user name string for logged in users can be vulnerable to XSS attacks, which affect the user themselves or an admin impersonating them. Admins can temporarily alter the welcome_banner.header.logged_in_members site text to remove the preferred_display_name placeholder, or not impersonate any users for the time being. This vulnerability is fixed in 3.5.0.beta8.
Weakness: CWE-79
Which versions are affected by CVE-2025-54411?
1 open source package ship an affected version, including discourse. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | All versions | 3.5.0 |
Products include Discourse Discourse.
How do I fix CVE-2025-54411?
Upgrade discourse to 3.5.0 or later.
Escape output for the context it lands in and set a strict Content Security Policy. Upgrading the affected component is the real fix. More about Cross-site scripting.
Is CVE-2025-54411 being exploited?
There is no known exploitation of CVE-2025-54411 in the wild and no public exploit code.
Other vulnerabilities in Discourse Discourse
- CVE-2021-41163 RCE via malicious SNS subscription payload
- CVE-2022-36066 Discourse vulnerable to RCE via admins uploading maliciously zipped file
- CVE-2022-39356 Discourse user account takeover via email and invite link
- CVE-2023-22468 Discourse vulnerable to Cross-site Scripting in local oneboxes
- CVE-2026-27934 Discourse leaks private topic title and post excerpt via user action API endpoint
Sources
Also known as BIT-discourse-2025-54411, GHSA-5mm6-j5vq-6884.