Discourse vulnerable to RCE via admins uploading maliciously zipped file
Priority MEDIUM 45CWE-434Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- High
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- Fixed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-434.
Summary
Discourse is an open source discussion platform. In versions prior to 2.8.9 on the `stable` branch and prior to 2.9.0.beta10 on the `beta` and `tests-passed` branches, admins can upload a maliciously crafted Zip or Gzip Tar archive to write files at arbitrary locations and trigger remote code execution. The problem is patched in version 2.8.9 on the `stable` branch and version 2.9.0.beta10 on the `beta` and `tests-passed` branches. There are no known workarounds.
Why it matters now
Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.02077 81st percentileScored 2026-11-07
Fix Fixed discourse (discourse): 2.8.9, 2.9.0.beta10
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- None
- Automatable
- No
- Technical impact
- Total
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 2.8.9; 2.9.0.beta0 to before 2.9.0.beta10 | 2.8.9, 2.9.0.beta10 | Patch available | CNA |
- discourse Vendordiscourse Affected before 2.8.9; 2.9.0.beta0 to before 2.9.0.beta10 Fixed in 2.8.9, 2.9.0.beta10 Patch available CNA
CPE configurations NVD · 10
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* | before 2.8.9 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta1:*:*:*:*:*:* | 2.9.0 beta1 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta2:*:*:*:*:*:* | 2.9.0 beta2 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta3:*:*:*:*:*:* | 2.9.0 beta3 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta4:*:*:*:*:*:* | 2.9.0 beta4 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta5:*:*:*:*:*:* | 2.9.0 beta5 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta6:*:*:*:*:*:* | 2.9.0 beta6 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta7:*:*:*:*:*:* | 2.9.0 beta7 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta8:*:*:*:*:*:* | 2.9.0 beta8 | Vulnerable | discourse |
| cpe:2.3:a:discourse:discourse:2.9.0:beta9:*:*:*:*:*:* | 2.9.0 beta9 | Vulnerable | discourse |
- cpe:2.3:a:discourse:discourse:*:*:*:*:*:*:*:* Versions before 2.8.9 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta1:*:*:*:*:*:* Versions 2.9.0 beta1 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta2:*:*:*:*:*:* Versions 2.9.0 beta2 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta3:*:*:*:*:*:* Versions 2.9.0 beta3 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta4:*:*:*:*:*:* Versions 2.9.0 beta4 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta5:*:*:*:*:*:* Versions 2.9.0 beta5 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta6:*:*:*:*:*:* Versions 2.9.0 beta6 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta7:*:*:*:*:*:* Versions 2.9.0 beta7 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta8:*:*:*:*:*:* Versions 2.9.0 beta8 Vulnerable ·discourse
- cpe:2.3:a:discourse:discourse:2.9.0:beta9:*:*:*:*:*:* Versions 2.9.0 beta9 Vulnerable ·discourse
Remediation
- Fix · CNA discourse (discourse) Fixed in 2.8.9, 2.9.0.beta10
Timeline
- 2026-10-02 Threatist record created from CVE-2022-36066
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