CVE-2022-39356Network attack vector

Account takeover via unbound reusable invite email

Published Nov 2, 2022 · Updated Apr 23, 2025

Improper authorization in Discourse 2.8.9 and earlier and 2.9.0.beta10 and earlier allows remote attackers to take over non-admin accounts. The invitation redemption flow accepts a submitted email address for a reusable invite and logs the redeemer into a matching existing account without binding the invite to that address. Exploitation requires a reusable invitation link, which by default can be generated only by trust-level-2 users; administrator accounts are excluded.

CVSS severity8.9
High
EPSS probability0.60%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Improper authorization in Discourse 2.8.9 and earlier and 2.9.0.beta10 and earlier allows remote attackers to take over non-admin accounts. The invitation redemption flow accepts a submitted email address for a reusable invite and logs the redeemer into a matching existing account without binding the invite to that address. Exploitation requires a reusable invitation link, which by default can be generated only by trust-level-2 users; administrator accounts are excluded.

The record

CVE
CVE-2022-39356
Published
Nov 2, 2022
Updated
Apr 23, 2025
Vendor
Discourse
Product
Discourse
Classifications
CWE-285, T1078
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Nov 2, 2022CVE publishedPublication date reported by the CVE source.
  2. Apr 23, 2025Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Compare these published version ranges with your installed build and any vendor patches.

  1. Affected versionversion=<= 2.8.9
  2. Affected versionversion=<= 2.9.0.beta10

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Discourse · Discourseversion=<= 2.8.9; version=<= 2.9.0.beta10

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
8.9GitHub, Inc.CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:L

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 9, 2026Sep 15, 2026
Latest reporting daySep 15, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-285Improper Authorization
T1078Valid Accounts

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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