Discourse: Cross-Site Data Exposure via Backup Restore Metacommand Injection in Multisite Deployments
Priority LOW 25CWE-77Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- High
- Attack requirements
- None
- Impact type
- Code execution
- Confidentiality · integrity · availability
- Low · None · None
- Fix status
- Fixed
Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-77.
Summary
Discourse is an open-source community discussion platform. In versions 3.5.0 and below, malicious meta-commands could be embedded in a backup dump and executed during restore. In multisite setups, this allowed an admin of one site to access data or credentials from other sites. This issue is fixed in version 3.5.1.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.00297 22nd percentileScored 2026-11-07
Fix Fixed discourse (discourse): 3.5.1
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| discourse | discourse | before 3.5.1 | 3.5.1 | Patch available | CNA |
- discourse Vendordiscourse Affected before 3.5.1 Fixed in 3.5.1 Patch available CNA
Remediation
- Fix · CNA discourse (discourse) Fixed in 3.5.1
Timeline
- 2026-10-02 Threatist record created from CVE-2025-59337
References
More Discourse vulnerabilities
- TI-2021-19656 Denial of Service in discourse CVSS 3.1MEDIUM 6.8
- TI-2024-36150 Potential Backup file leaked via Nginx in Discourse CVSS 3.1HIGH 7.5
- TI-2021-18002 RCE via malicious SNS subscription payload CVSS 3.1CRITICAL 10.0
- TI-2026-24651 Discourse: Open redirect via `sso_destination_url` cookie in `enter` CVSS 4.0MEDIUM 5.1
- TI-2026-22278 Discourse leaks private topic title and post excerpt via user action API endpoint CVSS 4.0HIGH 8.7
- TI-2023-24152 Unauthenticated access to new private chat messages in Discourse CVSS 3.1HIGH 7.5
Sources
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences