CVE-2023-28998: Nextcloud Desktop client misbehaves with E2EE when the server returns empty list of metadata keys

Published Apr 4, 2023
·
Updated

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.6.5, 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.​ Users should upgrade the Nextcloud Desktop client to 3.6.5 to receive a patch. No known workarounds are available.

Other sources

The Nextcloud Desktop Client is a tool to synchronize files from Nextcloud Server. Starting with version 3.0.0 and prior to version 3.6.5, 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.? Users should upgrade the Nextcloud Desktop client to 3.6.5 to receive a patch. No known workarounds are available.

Affected Software

1 affected component
Nextcloud Desktop>=3.0.0<3.6.5

Event History

Apr 4, 2023
CVE Published
via MITRE·12:45 PM
Data Sourced
via MITRE·12:45 PM
DescriptionSeverityWeakness
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Frequently Asked Questions

1

What is CVE-2023-28998?

CVE-2023-28998 is a vulnerability in the Nextcloud Desktop Client that allows a malicious server administrator to gain full access to an end-to-end encrypted folder.

2

What is the severity of CVE-2023-28998?

The severity of CVE-2023-28998 is medium, with a severity value of 6.1.

3

How does CVE-2023-28998 affect Nextcloud Desktop Client?

CVE-2023-28998 affects Nextcloud Desktop Client versions 3.0.0 to 3.6.5, allowing a malicious server administrator to decrypt files, recover the folder structure, and add new files.

4

Is there a fix for CVE-2023-28998?

Yes, a fix for CVE-2023-28998 is available in version 3.6.5 of the Nextcloud Desktop Client.

5

Where can I find more information about CVE-2023-28998?

More information about CVE-2023-28998 can be found in the ETH Zurich report and the Nextcloud Desktop Client GitHub pull request and security advisories.

Contact

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