Discourse welcome banner user name XSS
Priority LOW 12CWE-79Published · Updated
Key facts
- Attack vector
- Local
- Privileges required
- Low
- User interaction
- Passive
- Attack complexity
- Low
- Attack requirements
- None
- Impact type
- Cross-site scripting
- Confidentiality · integrity · availability
- Low · Low · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-79.
Summary
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.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00205 10th percentileScored 2026-11-07
Fix Fixed discourse (discourse): 3.5.0.beta8
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| discourse | discourse | before 3.5.0.beta8 | 3.5.0.beta8 | Patch available | CNA |
- discourse Vendordiscourse Affected before 3.5.0.beta8 Fixed in 3.5.0.beta8 Patch available CNA
CPE configurations NVD · 8
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:* | before 3.5.0 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta1:*:*:beta:*:*:* | 3.5.0 beta1 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta2:*:*:beta:*:*:* | 3.5.0 beta2 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta3:*:*:beta:*:*:* | 3.5.0 beta3 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta4:*:*:beta:*:*:* | 3.5.0 beta4 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta5:*:*:beta:*:*:* | 3.5.0 beta5 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta6:*:*:beta:*:*:* | 3.5.0 beta6 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.5.0:beta7:*:*:beta:*:*:* | 3.5.0 beta7 | Vulnerable | discourse |
- cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:* Versions before 3.5.0 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta1:*:*:beta:*:*:* Versions 3.5.0 beta1 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta2:*:*:beta:*:*:* Versions 3.5.0 beta2 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta3:*:*:beta:*:*:* Versions 3.5.0 beta3 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta4:*:*:beta:*:*:* Versions 3.5.0 beta4 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta5:*:*:beta:*:*:* Versions 3.5.0 beta5 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta6:*:*:beta:*:*:* Versions 3.5.0 beta6 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.5.0:beta7:*:*:beta:*:*:* Versions 3.5.0 beta7 Vulnerable ·discourse
Remediation
- Fix · CNA discourse (discourse) Fixed in 3.5.0.beta8
Timeline
- 2026-10-02 Threatist record created from CVE-2025-54411
References
More Discourse vulnerabilities
- TI-2021-19656 Denial of Service in discourse CVSS 3.1MEDIUM 6.8
- TI-2024-36150 Potential Backup file leaked via Nginx in Discourse CVSS 3.1HIGH 7.5
- TI-2021-18002 RCE via malicious SNS subscription payload CVSS 3.1CRITICAL 10.0
- TI-2026-24651 Discourse: Open redirect via `sso_destination_url` cookie in `enter` CVSS 4.0MEDIUM 5.1
- TI-2026-22278 Discourse leaks private topic title and post excerpt via user action API endpoint CVSS 4.0HIGH 8.7
- TI-2023-24152 Unauthenticated access to new private chat messages in Discourse CVSS 3.1HIGH 7.5
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences