CVE-2022-39356 — Discourse is a platform for community discussion

Discourse is a platform for community discussion. Users who receive an invitation link that is not scoped to a single email address can enter any non-admin user's email and gain access to their account when accepting the invitation. All users should upgrade to the latest ver

01What is this vulnerability?

Discourse is a platform for community discussion. Users who receive an invitation link that is not scoped to a single email address can enter any non-admin user's email and gain access to their account when accepting the invitation. All users should upgrade to the latest version. A workaround is temporarily disabling invitations with `SiteSetting.max_invites_per_day = 0` or scope them to…

02Affected products

Vendor	Product	Versions
discourse	discourse	<= 2.8.9, <= 2.9.0.beta10

03Active exploitation status

Not currently listed on the CISA Known Exploited Vulnerabilities (KEV) catalog. EPSS is the best forward-looking signal — see the EPSS row above.

04Recommended remediation

• Patch to a fixed version listed in the vendor advisory (see references below).
• Mitigate with WAF rules, network egress filters, or feature flags where the patch is not yet available.
• Hunt historical logs for exploitation indicators — see Detection signatures below.

05Technical details

For the full vendor write-up, exploit chains, and reference implementations, see the references list in section 09.

06Detection signatures

Ask SARA in chat to draft a starting detection for this CVE in your stack of choice.

07Related CVEs

No directly-cited follow-up CVEs in the KB record for this advisory. The references list in section 09 carries the vendor cross-references.

08Timeline

• Published: 2022-11-02T00:00:00.000Z
• Last modified: 2025-04-23T16:41:45.660Z

09References

• github.com — https://github.com/discourse/discourse/security/advisories/GHSA-x8w7-rwmr-w278
• github.com — https://github.com/discourse/discourse/pull/18817