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Vulnerability record · CVE-2021-41163 · published 20 October 2021

CVE-2021-41163: Discourse injection vulnerability

Discourse · Discourse

Discourse is an open source platform for community discussion. In affected versions maliciously crafted requests could lead to remote code execution. This resulted from a lack of validation in subscribe_url values. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. To workaround the issue without updating, requests with a path starting /webhooks/aws path could be blocked at an upstream proxy.

9.8 CVSS 3.1 Critical EPSS 20% · top 2.7% CWE-74 · Injection
9.8CVSS 3.1 base score, v2 7.5
20%EPSS exploitation probability, 30 days
NoNot in CISA KEV
1Affected product versions listed by NVD
4References
17 Jun 2026Last modified by NVD

Description

Discourse is an open source platform for community discussion. In affected versions maliciously crafted requests could lead to remote code execution. This resulted from a lack of validation in subscribe_url values. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. To workaround the issue without updating, requests with a path starting /webhooks/aws path could be blocked at an upstream proxy.

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

Affected products

1 vulnerable configurations from NVD's CPE data, grouped by vendor and product.

References

LinkTags
https://github.com/discourse/discourse/commit/fa3c46cf079d28b086fe1025349bb00223a5d5e9 PatchThird Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-jcjx-pvpc-qgwq Third Party Advisory
https://github.com/discourse/discourse/commit/fa3c46cf079d28b086fe1025349bb00223a5d5e9 PatchThird Party Advisory
https://github.com/discourse/discourse/security/advisories/GHSA-jcjx-pvpc-qgwq Third Party Advisory

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Related vulnerabilities

Same products first, then exploited flaws of the same weakness class.

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Source: NIST National Vulnerability Database (record CVE-2021-41163), CISA KEV, FIRST EPSS (scores of 2026-09-27). This page is refreshed as NVD updates the record.