DiscourseApplication

CVE-2023-22739

MEDIUM · 6.5 CVSS v3.1 Published 2023-01-26
Fix available
A fix is available. Upgrade to 3.0.1 or later.
See remediation →
71/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Discourse is an open source platform for community discussion. Versions prior to 3.0.1 (stable), 3.1.0.beta2 (beta), and 3.1.0.beta2 (tests-passed) are subject to Allocation of Resources Without Limits or Throttling. As there is no limit on data contained in a draft, a malicious user can create an arbitrarily large draft, forcing the instance to a crawl. This issue is patched in versions 3.0.1 (stable), 3.1.0.beta2 (beta), and 3.1.0.beta2 (tests-passed). There are no workarounds.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · high confidence

Discourse versions prior to 3.0.1 lack limits on draft data size, allowing authenticated users to create arbitrarily large drafts. A malicious user can exhaust server resources by creating oversized drafts, causing the instance to become unresponsive (denial of service).

MitigationUpgrade to Discourse version 3.0.1 (stable) or 3.1.0.beta2 or later, which implements proper limits on draft data size to prevent resource exhaustion.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
DiscourseApplication
Affected:< 3.0.1= 3.1.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
None
Availability
High

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

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Check Discourse version
    Run `git -C /var/discourse/repo describe --tags` or check the admin dashboard under /about for the exact version number
    Affected if Version is less than 3.0.1 or equals 3.1.0 (the vulnerable versions)
  2. Verify drafts are accessible to authenticated users
    Check if the /drafts endpoint is enabled by reviewing Discourse site settings at /admin/site_settings or by attempting to access drafts as a logged-in user
    Affected if Authenticated users can access the draft creation feature (this is enabled by default in most installations)
  3. Inspect database for abnormally large drafts
    Connect to the Discourse database and run: SELECT id, user_id, LENGTH(stripped) as size FROM drafts ORDER BY size DESC LIMIT 10;
    Affected if Any draft records exist with a payload size exceeding reasonable limits (e.g., > 1MB) indicating exploitation or vulnerability presence

You are affected if your Discourse version is below 3.0.1 (or is exactly 3.1.0), authenticated users can create drafts, and large draft records exist in your database.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

dbcve · scoped
Upgrade available Upgrade to 3.0.1 or later
Fixed in 3.0.1
Interim mitigation

Upgrade to Discourse version 3.0.1 (stable) or 3.1.0.beta2 or later, which implements proper limits on draft data size to prevent resource exhaustion.

Recommended fix High confidence

3.0.1 (stable) or 3.1.0.beta2 (beta/tests-passed)

  1. Verify current Discourse version using the admin dashboard or CLI
  2. Schedule a maintenance window for the upgrade
  3. Backup the Discourse database and uploaded files
  4. For stable channel: upgrade to version 3.0.1 or later
  5. For beta/tests-passed channel: upgrade to version 3.1.0.beta2 or later
  6. After upgrade, verify the application is functioning correctly
  7. Confirm the fix by testing draft creation with large content

Generated from the published advisory — verify against the referenced sources before acting.

Fix this in Discourse Scoped from the published advisory
  • Consultation1.0 h
  • Implementation2.0 h
  • Testing2.0 h
  • Review / QA1.0 h
6.0 hours of engineering $1,040
Get the upgrade done

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $1,664.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2023-22739 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2023-22739 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data