Multisite denial of service through unsanitized dynamic dispatch to SiteSetting in Discourse
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- —
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA.
Summary
Discourse is an open source platform for community discussion. In affected versions a user logged as an administrator can call arbitrary methods on the `SiteSetting` class, notably `#clear_cache!` and `#notify_changed!`, which when done on a multisite instance, can affect the entire cluster resulting in a denial of service. Users not running in multisite environments are not affected. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. There are no known workarounds for this vulnerability.
Why it matters now
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 | stable: < 3.0.2; beta: < 3.1.0.beta3 | — | No fix listed | CNA |
- discourse Vendordiscourse Affected stable: < 3.0.2; beta: < 3.1.0.beta3 Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:* | up to 3.0.1 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:* | before 3.1.0 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.1.0:beta1:*:*:beta:*:*:* | 3.1.0 beta1 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:* | 3.1.0 beta2 | Vulnerable | discourse |
- cpe:2.3:a:discourse:discourse:*:*:*:*:stable:*:*:* Versions up to 3.0.1 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:*:*:*:*:beta:*:*:* Versions before 3.1.0 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.1.0:beta1:*:*:beta:*:*:* Versions 3.1.0 beta1 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:3.1.0:beta2:*:*:beta:*:*:* Versions 3.1.0 beta2 Vulnerable ·discourse
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2023-30606
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