What is CVE-2023-37904?

CVE-2023-37904 is a low-severity vulnerability in Discourse, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 2.6/10. Published 2023-07-28.

How severe is CVE-2023-37904?

Low severity. CVSS v3 base score is 2.6 out of 10.

Vulnerability in Discourse

CVE-2023-37904

Discourse is an open source discussion platform. Prior to version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches, more users than permitted could be created from invite links. The issue is patched in version 3.0.6 of the `stable` branch and version 3.1.0.beta7 of the `beta` and `tests-passed` branches. As a workaround, use restrict to email address invites.

Vulnerability class: Race Condition

Published 2023-07-28 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 2.6 (Low). Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:R/S:U/C:L/I:N/A:N.

EPSS exploit prediction

EPSS: 0.003 (17.9th percentile), scored 2026-10-02.

Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 18th percentile — 17.9% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.003 · newest: 0.003 · change: 0.000

Affected products

Discourse — versions 2.4.0, 3.1.0, 2.9.0

Weakness classification (CWE)

CWE-362 — Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition)

References

github.com/discourse/discourse/security/advisories/GHSA-6wj5-4ph2-c7qg (Vendor Advisory)
github.com/discourse/discourse/commit/62a609ea2d0645a27ee8adbb01ce10a5e03a600b (Patch)

Frequently asked questions

What is CVE-2023-37904?: CVE-2023-37904 is a low-severity vulnerability in Discourse, classified under Concurrent Execution using Shared Resource with Improper Synchronization (Race Condition). CVSS score: 2.6/10. Published 2023-07-28.
How severe is CVE-2023-37904?: Low severity. CVSS v3 base score is 2.6 out of 10.