Users can delete external storage mount points

7.7 CVSS

Vulnerability Description

Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 19.0.0 and prior to versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, a malicious user could delete any personal or global external storage, making them inaccessible for everyone else as well. Nextcloud server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. As a workaround, disable app files_external. This also makes the external storage inaccessible but retains the configurations until a patched version has been deployed.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

nextcloud

View all reports →

Affected Software

security-advisories

Vulnerable Versions:

>= 19.0.0, < 19.0.13.10, >= 20.0.0, < 20.0.14.15, >= 21.0.0, < 21.0.9.13, >= 22.0.0, < 22.2.10.14, >= 23.0.0, < 23.0.12.9, >= 24.0.0, < 24.0.12.5, >= 25.0.0, < 25.0.9, >= 26.0.0, < 26.0.4, >= 27.0.0, < 27.0.1