title: Users can delete external storage mount points
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.
problem types: CWE-284: Improper Access Control
affected:
{
vendor: nextcloud
product: security-advisories
versions:
version: >= 19.0.0, < 19.0.13.10, status: affected
version: >= 20.0.0, < 20.0.14.15, status: affected
version: >= 21.0.0, < 21.0.9.13, status: affected
version: >= 22.0.0, < 22.2.10.14, status: affected
version: >= 23.0.0, < 23.0.12.9, status: affected
version: >= 24.0.0, < 24.0.12.5, status: affected
version: >= 25.0.0, < 25.0.9, status: affected
version: >= 26.0.0, < 26.0.4, status: affected
version: >= 27.0.0, < 27.0.1, status: affected
}
metrics:
cvssV3_1: [
attackComplexity: LOW
attackVector: NETWORK
availabilityImpact: HIGH
baseScore: 7.7
baseSeverity: HIGH
confidentialityImpact: NONE
integrityImpact: NONE
privilegesRequired: LOW
scope: CHANGED
userInteraction: NONE
vectorString: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H
version: 3.1
]