CVE-2024-53991
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 · uneditedDiscourse is an open source platform for community discussion. This vulnerability only impacts Discourse instances configured to use `FileStore::LocalStore` which means uploads and backups are stored locally on disk. If an attacker knows the name of the Discourse backup file, the attacker can trick nginx into sending the Discourse backup file with a well crafted request. This issue is patched in the latest stable, beta and tests-passed versions of Discourse. Users are advised to upgrade. Users unable to upgrade can either 1. Download all local backups on to another storage device, disable the `enable_backups` site setting and delete all backups until the site has been upgraded to pull in the fix. Or 2. Change the `backup_location` site setting to `s3` so that backups are stored and downloaded directly from S3.
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 confidenceThis is an information disclosure vulnerability in Discourse where an attacker who knows the name of a backup file can craft a malicious request to trick nginx into serving the local backup file. Only Discourse instances configured to use FileStore::LocalStore (local disk storage for backups) are affected.
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< 3.3.2< 3.4.0= 3.4.0CVSS 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
- High
- Privileges
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality
- High
- Integrity
- None
- Availability
- None
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:N/A:N
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 checksWork through these to decide whether this CVE applies to you.
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Check Discourse versionAccess the admin dashboard and navigate to /about or check the version displayed in the admin panel footer. Alternatively, check the VERSION file in the Discourse installation directory if you have direct server access.Affected if The installed version is lower than 3.3.2, or between 3.4.0 and 3.4.0 (inclusive). Versions 3.3.2 and above, or 3.4.1 and above are not affected.
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Verify backup storage configurationIn the Discourse admin panel, go to the backup settings and check the backup_location site setting. This setting controls where backups are stored.Affected if The backup_location is set to local or a local filesystem path, which indicates FileStore::LocalStore is in use. If set to S3 or another remote storage, the instance is not affected by this specific vulnerability.
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Confirm nginx serves backup directoryCheck the nginx configuration file for your Discourse instance. Look for any location blocks that may allow access to the backup directory path. Inspect the containers/nginx.conf or the deployed nginx configuration.Affected if Nginx is configured to serve files from the local backup directory and the backup_location is set to local storage.
You are affected if your Discourse version is less than 3.3.2, or exactly 3.4.0, AND you have backup_location configured to use local disk storage.
Generated from the published advisory. Verify against your own configuration.
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 · scoped3.3.23.4.0
Upgrade to the latest stable, beta, or tests-passed version of Discourse. Alternatively, migrate backup storage from local disk to S3 using the backup_location site setting, or download backups externally and disable local backups until the fix is applied.
Latest stable Discourse release (3.3.2 or newer)
- 1. Identify your current Discourse version by checking the admin panel or running `./discourse versions`
- 2. Upgrade to the latest stable Discourse release (currently 3.3.2 or later stable version)
- 3. After upgrade, verify the fix is applied by confirming your Discourse version is no longer in the affected range: not < 3.3.2, not < 3.4.0, and not = 3.4.0
- 4. Alternative if unable to upgrade: Download all local backups to external storage, then disable the `enable_backups` site setting and delete all local backup files until the upgrade can be performed
- 5. Alternative mitigation: Change the `backup_location` site setting from `local` to `s3` to store backups on S3 instead of local disk
Generated from the published advisory — verify against the referenced sources before acting.
- Consultation3.0 h
- Implementation4.0 h
- Testing2.0 h
- Review / QA1.0 h
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Scan for this in your stack
Free · runs locallyCheck whether your project pulls in CVE-2024-53991 — 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 sourcesPractitioner notes
ContributedPeer-ranked notes from engineers who’ve handled CVE-2024-53991 in production — separate from our analysis above.
The advisory tells you what broke. It rarely tells you what actually worked. If you’ve dealt with this one, that detail is what the next engineer is searching for.
- The version that genuinely resolved it — not the one the vendor claimed
- A config change or rule that shut the vector down
- A gotcha in the upgrade path that cost you an afternoon
No notes yet
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- Version or environment caveats, and links to real fixes
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