# CVE-2024-53991: Potential Backup file leaked via Nginx in Discourse

- Exploited (CISA KEV): no
- Published: 2024-12-19
- CVSS: 7.5 HIGH (v3.1)
- EPSS: 29.9% (98th percentile)
- CWE: CWE-200

Discourse 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.

## Edge WAF coverage (claimed by vendors, not measured)

| Vendor | Status | First rule | Days after publication |
|---|---|---|---|
| Cloudflare | Before feed history | — | — |
| AWS | No public claim | — | — |
| Microsoft Azure | No public claim | — | — |
| Google Cloud | No public claim | — | — |
| Fastly | Before feed history | — | — |
| F5 | Rule published | 2025-05-22 | 154 |
| Akamai | No public source | — | — |
| OWASP CRS | No public claim | — | — |

### F5

- 2025-05-22 · new · rule 200009328
  > Added: signature 200009328 "Discourse Backup File Information Disclosure" (Information Leakage, risk Medium), systems: Ruby. References: CVE-2024-53991.
  Source: https://docs.cloud.f5.com/docs-v2/platform/changelogs/security-details-changelog

## Our test (measured)

- OWASP Core Rule Set 4.25.0, paranoia level 1, anomaly threshold 5, default CRS settings: passed (0 of 2 requests blocked), template CVE-2024-53991, 2026-11-02
- OWASP Core Rule Set 4.25.0, paranoia level 2, anomaly threshold 5, default CRS settings: passed (0 of 2 requests blocked), template CVE-2024-53991, 2026-11-02

"No public claim" means no vendor statement names this CVE; "Before feed history" means the CVE is older than the vendor feed. In both cases generic rules may still block it.

HTML: https://cve.vigilbase.com/cve/CVE-2024-53991 · JSON: https://cve.vigilbase.com/api/v1/cves/CVE-2024-53991