Nextcloud E2E Encrypted Folder Leak (Desktop <=3.8, Android <=3.25, iOS <=4.8)
CVE-2023-28999 Published on April 4, 2023
Nextcloud: Lack of authenticity of metadata keys allows a malicious server to gain access to E2EE folders
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.
Vulnerability Analysis
CVE-2023-28999 can be exploited with physical access, requires user interaction and user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have a high impact on confidentiality and integrity, and a small impact on availability.
Weakness Type
Missing Cryptographic Step
The product does not implement a required step in a cryptographic algorithm, resulting in weaker encryption than advertised by the algorithm.
Products Associated with CVE-2023-28999
stack.watch emails you whenever new vulnerabilities are published in Nextcloud Desktop or Nextcloud. Just hit a watch button to start following.
Affected Versions
nextcloud security-advisories:- Version >= 3.0.0, < 3.8.0 is affected.
- Version >= 3.13.0, < 3.25.0 is affected.
- Version >= 3.0.5, < 4.8.0 is affected.
Exploit Probability
EPSS (Exploit Prediction Scoring System) scores estimate the probability that a vulnerability will be exploited in the wild within the next 30 days. The percentile shows you how this score compares to all other vulnerabilities.