Is CVE-2026-45264 exploited in the wild?

No. Junglewise Threat Intelligence has no report of CVE-2026-45264 being exploited in the wild.

How severe is CVE-2026-45264?

Medium severity, with a CVSS score of 4.3, published 1 June 2026.

Which products and versions are affected?

Nextcloud Groupfolders 17.0.0 to < 17.0.15, 18.0.0 to < 18.1.12, 19.0.0 to < 19.1.16, 20.0.0 to < 20.1.11, 21.0.0 to < 21.0.4.

Is there a fix for CVE-2026-45264?

A patch was published on 2026-02-09: Fix merged into master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

How is CVE-2026-45264 attacked?

It is attacked over the network, in a network appliance.

Am I affected by CVE-2026-45264?

Check whether you run Nextcloud Groupfolders at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-45264: Nextcloud Team Folders improper access control in file renaming

Q: Is there a fix for CVE-2026-45264?

A patch was published on 2026-02-09: Fix merged into master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

Q: How is CVE-2026-45264 attacked?

It is attacked over the network, in a network appliance.

Q: Am I affected by CVE-2026-45264?

Check whether you run Nextcloud Groupfolders at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

CVE-2026-45264 · Severity: medium · CVSS 4.3 · Published 2026-06-01

Nextcloud is a content collaboration platform used by organizations to store and share files. A flaw in the Team Folders application allows users who only have permission to read and create files to also rename existing files, even if they lack the specific permission to modify them. This could lead to unauthorized reorganization of shared data or disruption of file-based workflows.

Vendors: Nextcloud.

Quick answers

Is CVE-2026-45264 exploited in the wild?: No. Junglewise Threat Intelligence has no report of CVE-2026-45264 being exploited in the wild.
How severe is CVE-2026-45264?: Medium severity, with a CVSS score of 4.3, published 1 June 2026.
Which products and versions are affected?: Nextcloud Groupfolders 17.0.0 to < 17.0.15, 18.0.0 to < 18.1.12, 19.0.0 to < 19.1.16, 20.0.0 to < 20.1.11, 21.0.0 to < 21.0.4.
Is there a fix for CVE-2026-45264?: A patch was published on 2026-02-09: Fix merged into master branch Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.
How is CVE-2026-45264 attacked?: It is attacked over the network, in a network appliance.
Am I affected by CVE-2026-45264?: Check whether you run Nextcloud Groupfolders at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Technical details

An improper access control vulnerability (CWE-284) exists in the Nextcloud Team Folders (Groupfolders) application. The vulnerability stems from insufficient validation of Access Control List (ACL) rules when processing file rename requests. Specifically, the application fails to verify that a user possesses 'UPDATE' permissions before allowing a rename operation, provided the user already has 'READ' and 'CREATE' permissions. An authenticated attacker with network access to the Nextcloud instance can exploit this to rename files in shared team folders where they should only have read/create access. The issue is resolved in versions 17.0.15, 18.1.12, 19.1.16, 20.1.11, and 21.0.4.

Affected products

Nextcloud Team Folders (Groupfolders) 17.0.0 to < 17.0.15, 18.0.0 to < 18.1.12, 19.0.0 to < 19.1.16, 20.0.0 to < 20.1.11, 21.0.0 to < 21.0.4

Timeline

2026-02-09: patched: Fix merged into master branch
2026-05-12: advisory: GitHub Security Advisory published
2026-06-01: disclosed: CVE published to NVD

References

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