Attacker can obtain write access to any federated share/public link
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- High · High · None
- Fix status
- Fixed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-639.
Summary
Nextcloud Server is a Nextcloud package that handles data storage. In versions prior to 19.0.11, 20.0.10, and 21.0.2, an attacker is able to receive write/read privileges on any Federated File Share. Since public links can be added as federated file share, this can also be exploited on any public link. Users can upgrade to patched versions (19.0.11, 20.0.10 or 21.0.2) or, as a workaround, disable federated file sharing.
Why it matters now
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 | security-advisories | before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2 | 19.0.11, 20.0.10, 21.0.2 | Patch available | CNA |
- security-advisories Vendornextcloud Affected before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2 Fixed in 19.0.11, 20.0.10, 21.0.2 Patch available CNA
CPE configurations NVD · 1
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* | before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2 | Vulnerable | nextcloud |
- cpe:2.3:a:nextcloud:nextcloud_server:*:*:*:*:*:*:*:* Versions before 19.0.11; 20.0.0 to before 20.0.10; 21.0.0 to before 21.0.2 Vulnerable ·nextcloud
Remediation
- Fix · CNA security-advisories (nextcloud) Fixed in 19.0.11, 20.0.10, 21.0.2
Timeline
- 2026-10-02 Threatist record created from CVE-2021-32654
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
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences