CVE-2026-45285: Nextcloud: Hidden Public Link creation when sharing to a Team External Member

Severity: medium (CVSS 6.4 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.3% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-06-01 · updated 2026-07-22
Weakness: CWE-862

Description

Nextcloud is an open source content collaboration platform. From versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, when a user shares a folder or file with a Nextcloud Team that includes an external member (a person added via email address who does not have a Nextcloud account), the system automatically creates a public link for that external member. This public link is not displayed in the share section of the folder, so the folder owner has no knowledge of its existence. It is sent via email to the external member. It grants the same permissions (read, write, delete, reshare, download) as the Team’s access. An attacker who receives or intercepts this link can access, modify, delete, reshare, and download all data in the shared folder without any further authentication. The folder owner cannot see or revoke the link through the normal sharing interface. This issue has been patched in versions 32.0.9 and 33.0.3.

Affected products

Nextcloud Server: from 32.0.0 before 32.0.9; from 33.0.0 before 33.0.3 — fixed in 32.0.9, 33.0.3

How to fix

Upgrade to a fixed version: Nextcloud Server 32.0.9, 33.0.3. Check the vendor advisory for mitigations.

References

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