Server-side request forgery in Nextcloud Server
Priority LOW 32CWE-918Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- Low
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Information disclosure
- Confidentiality · integrity · availability
- High · None · None
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-918 and the CVSS impact.
Summary
A missing check for IPv4 nested inside IPv6 in Nextcloud server < 17.0.1, < 16.0.7, and < 15.0.14 allowed a Server-Side Request Forgery (SSRF) vulnerability when subscribing to a malicious calendar URL.
Why it matters now
EPSS 0.01395 72nd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | Nextcloud Server | Fixed in 17.0.2, 16.0.7, and 15.0.14 | — | No fix listed | CNA |
- Nextcloud Server Vendor— Affected Fixed in 17.0.2, 16.0.7, and 15.0.14 Fixed in — No fix listed CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* | before 15.0.14; 16.0.0 to before 16.0.7; 17.0.0 to before 17.0.2 | Vulnerable | nextcloud |
- cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* Versions before 15.0.14; 16.0.0 to before 16.0.7; 17.0.0 to before 17.0.2 Vulnerable ·nextcloud
Remediation
No fixed version listed by the sources yet.
Vendor assessments
Timeline
- 2026-10-02 Threatist record created from CVE-2020-8138
- 2026-10-03 Alias added: GHSA-27v9-58mg-8v43
References
More Nextcloud Server vulnerabilities
- TI-2023-20855 Users can delete external storage mount points CVSS 3.1HIGH 7.7
- TI-2023-11091 Nextcloud download permissions can be changed by resharer CVSS 3.1HIGH 7.5
- TI-2023-10624 Nextcloud Server vulnerable to SSRF via filter bypass due to lax checking on IPs CVSS 3.1MEDIUM 5.3
- TI-2025-37238 Cross-site scripting in Nextcloud CVSS 3.1MEDIUM 6.4
- TI-2023-11086 nextcloud vulnerable to Uncontrolled Resource Consumption CVSS 3.1MEDIUM 6.5
- TI-2022-18738 Exception logging in Sharepoint app reveals clear-text connection details CVSS 3.1MEDIUM 6.5
Sources
- CVE-2020-8138 · CVE Program
- CVE-2020-8138 · NVD
- FIRST EPSS
- GHSA-27v9-58mg-8v43 · GitHub Advisory Database · CC BY 4.0
- CVE-2020-8138 · Red Hat security data · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences