CVE-2023-28999

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

State: Published
Severity: 6.9 Medium
Published: Apr 4, 2023
Updated: Feb 11, 2025
Reserved: Mar 29, 2023

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.

Scores

CVSS	Score	Vector	Source
3.1	6.9 Medium	CVSS:3.1/AV:P/AC:L/PR:H/UI:R/S:C/C:H/I:H/A:L	GitHub_M

Weaknesses

CWE-325 Missing Cryptographic Step

Affected Products

Product	Versions
security-advisoriesnextcloud	>= 3.0.0, < 3.8.0Affected >= 3.13.0, < 3.25.0Affected >= 3.0.5, < 4.8.0Affected

References

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