Discourse
CVE-2024-53851
MEDIUM
Vulnerability Assessment
| Weakness |
CWE
OWASP Top 10:2025
A06:2025 - Insecure Design
ASVS 5.0
V2 - Validation and Business Logic Resource consumption limits
MITRE ATT&CK
1 technique across 1 tactic: Impact The technique list with ATT&CK links and the kill-chain view is part of the Basic plan and up. |
| Impact | CVSS score of 4.3 (MEDIUM). Attack characteristics: network attack vector, low complexity, low privileges required, no user interaction not required. EPSS exploitation probability: 0.18%. |
| Exploit ScenarioDerived | A remote attacker could cause denial of service by exhausting system resources by sending crafted requests to the affected application. |
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Alert meAnalysisAIv1 – Mar 28, 2026
Discourse is an open source platform for community discussion. Rated medium severity (CVSS 4.3), this vulnerability is remotely exploitable, low attack complexity. This Uncontrolled Resource Consumption vulnerability could allow attackers to cause denial of service by exhausting system resources.
RemediationAI
A vendor patch is available. Apply the latest security update as soon as possible. Implement rate limiting, set resource quotas, validate input sizes, use timeouts.
Affects your stack
Find out whether the stacks and servers you run are on an affected version.
Checking this CVE against your own stacks and servers is part of the Basic plan and up.
Technical ContextAI · show details
This vulnerability is classified as Uncontrolled Resource Consumption (CWE-400), which allows attackers to cause denial of service by exhausting system resources. 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. Affected products include: Discourse.
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- Exploit and PoC references, threat intelligence from 22 sources
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Severity by source
AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L
Primary rating from GitHub Advisory · only source for this CVE.
CVSS VectorGitHub Advisory
Lifecycle Timeline
2DescriptionGitHub Advisory
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.
Executive ViewAI
Organizations using affected should be aware of moderate risk from CVE-2024-53851, a resource exhaustion vulnerability rated CVSS 4.3. Service availability could be impacted. A patch is available and should be applied during regular vulnerability management.
Apply vendor patch. If patching is delayed: implement rate limiting and resource quotas.
Threat Intelligence Overview
NVD
CVE.org
EPSS
GitHub
How this decision was reached
The engine reads each signal below and applies a fixed list of rules from top to bottom. The first rule that matches sets the recommended action – like a statement, every line is shown.
What every action level means
SSVC AssessmentENISA
Priority Score
Attack Technique
Denial of Service attacks render applications or systems unavailable by overwhelming resources or triggering failure conditions.
Affected Products (CPE)GitHub Advisory
Discourse versions prior to 3.5.0.beta6 contain a reflected cross-site scripting (XSS) vulnerability in social login fun
discourse-bbcode is the official BBCode plugin for Discourse. Rated critical severity (CVSS 9.8), this vulnerability is
Unauthorized information disclosure in Discourse discussion platform versions prior to 2026.3.0-latest.1, 2026.2.1, and
Discourse is an open source platform for community discussion. Rated high severity (CVSS 8.2), this vulnerability is rem
Discourse versions prior to 2025.12.2, 2026.1.1, and 2026.2.0 contain an insecure direct object reference (IDOR) in the
In Discourse 2.7.0 through beta1, a rate-limit bypass leads to a bypass of the 2FA requirement for certain forms. Rated
Unauthenticated attackers can submit forged webhook payloads to multiple email provider integrations in Discourse versio
Discourse is an open-source discussion platform. Rated medium severity (CVSS 6.5), this vulnerability is remotely exploi
Discourse is an open source platform for community discussion. Rated medium severity (CVSS 5.9), this vulnerability is r
Discourse versions prior to 3.4.4 (stable), 3.5.0.beta5 (beta), and 3.5.0.beta6-dev (tests-passed) contain a critical vu
Discourse is an open source platform for community discussion. Rated critical severity (CVSS 9.8), this vulnerability is
Discourse Patreon enables syncronization between Discourse Groups and Patreon rewards. Rated critical severity (CVSS 9.8
Exploit-DB