Resource exhaustion in Discourse

CVE-2024-53851

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.

Vulnerability class: DoS (Denial of Service)

Published · last modified .

CVSS v3 metric

CVSS v3 base score 4.3 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L.

EPSS exploit prediction

EPSS: 0.005 (37.2th percentile), scored .

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 37th percentile — 37.2% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS trend (30 days)EPSS over the last 30 days for CVE-2024-53851: held from 0.005 to 0.005.

EPSS over last 30 days · oldest: 0.005 · newest: 0.005 · change: 0.000

Affected products

  • Discourse — versions beta: <= 3.4.0.beta3, 3.4.0, stable: <= 3.3.2

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2024-53851?
CVE-2024-53851 is a medium-severity vulnerability in Discourse, classified under Uncontrolled Resource Consumption. CVSS score: 4.3/10. Published 2025-02-04.
How severe is CVE-2024-53851?
Medium severity. CVSS v3 base score is 4.3 out of 10.