CVE-2024-53851 Partial denial of service via inline oneboxes in Discourse
Authenticated users can cause partial denial of service by submitting excessive URLs to the inline onebox generation endpoint.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2024-53851?
CVE-2024-53851 is a medium-severity denial of service vulnerability in Discourse Discourse, published on 4 Feb 2025. Any signed-in user can exploit it over the network, with no action from the victim.
Official description
Discourse is an open source platform for community discussion. In affected versions the endpoint for generating inline oneboxes for URLs wasn't enforcing limits on the number of URLs that it accepted, allowing a malicious user to inflict denial of service on some parts of the app. This vulnerability is only exploitable by authenticated users. This issue has been patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. Users unable to upgrade should turn off the `enable inline onebox on all domains` site setting and remove all entries from the `allowed inline onebox domains` site setting.
Weakness: CWE-400
Which versions are affected by CVE-2024-53851?
1 open source package ship an affected version, including discourse. It affects 1 product.
| Package | Affected | Fixed in |
|---|---|---|
discourse Bitnami | All versions | 3.3.3 |
Products include Discourse Discourse.
How do I fix CVE-2024-53851?
Upgrade discourse to 3.3.3 or later.
Upgrade, then put limits on request size, rate and nesting depth so one client cannot exhaust the service. More about Denial of service.
Is CVE-2024-53851 being exploited?
There is no known exploitation of CVE-2024-53851 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-2024-53851, GHSA-49rv-574x-wgpc.