CVE-2023-28999 - CVE House

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Status published Medium CVE-2023-28999

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

6.9 CVSS

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

More from nextcloud

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Affected Vendor

nextcloud

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Affected Software

security-advisories

Vulnerable Versions:

>= 3.0.0, < 3.8.0, >= 3.13.0, < 3.25.0, >= 3.0.5, < 4.8.0

Timeline

Official Publish: April 4th, 2023

Last Modified: February 11th, 2025

Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:L

Weaknesses (CWE)

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.