CVE-2023-28999: Nextcloud: Lack of authenticity of metadata keys allows a malicious server to gain access to E2EE folders

Published Apr 4, 2023
·
Updated

Nextcloud is an open-source productivity platform. In Nextcloud Desktop client 3.0.0 until 3.8.0, Nextcloud Android app 3.13.0 until 3.25.0, and Nextcloud iOS app 3.0.5 until 4.8.0, a malicious server administrator can gain full access to an end-to-end encrypted folder. They can decrypt files, recover the folder structure and add new files.​ This issue is fixed in Nextcloud Desktop 3.8.0, Nextcloud Android 3.25.0, and Nextcloud iOS 4.8.0. No known workarounds are available.

Other sources

Nextcloud is an open-source productivity platform. In Nextcloud Desktop client 3.0.0 until 3.8.0, Nextcloud Android app 3.13.0 until 3.25.0, and Nextcloud iOS app 3.0.5 until 4.8.0, a malicious server administrator can gain full access to an end-to-end encrypted folder. They can decrypt files, recover the folder structure and add new files.? This issue is fixed in Nextcloud Desktop 3.8.0, Nextcloud Android 3.25.0, and Nextcloud iOS 4.8.0. No known workarounds are available.

Affected Software

3 affected components
NextCloud Desktop>=3.0.0<3.8.0
Nextcloud Nextcloud>=3.0.5<4.8.0
Nextcloud Nextcloud>=3.13.0<3.25.0

Event History

Apr 4, 2023
CVE Published
via MITRE·12:51 PM
Data Sourced
via MITRE·12:51 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2023-28999?

CVE-2023-28999 is a vulnerability that allows a malicious server administrator to gain full access to an end-to-end encrypted folder in Nextcloud Desktop client, Nextcloud Android app, and Nextcloud iOS app.

2

What is the severity of CVE-2023-28999?

The severity of CVE-2023-28999 is medium, with a CVSS score of 6.4.

3

Which software versions are affected by CVE-2023-28999?

Nextcloud Desktop client versions 3.0.0 to 3.8.0, Nextcloud Android app versions 3.13.0 to 3.25.0, and Nextcloud iOS app versions 3.0.5 to 4.8.0 are affected by CVE-2023-28999.

4

How can a malicious server administrator exploit CVE-2023-28999?

A malicious server administrator can exploit CVE-2023-28999 to gain full access to an end-to-end encrypted folder and decrypt files.

5

Are there any references for CVE-2023-28999?

Yes, you can find references for CVE-2023-28999 at the following links: [link1], [link2], [link3].

Contact

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