CVE-2023-28998

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.

• CWE-325

• https://ethz.ch/content/dam/ethz/special-interest/infk/inst-infsec/appliedcrypto/education/theses/report_DanieleCoppola.pdfExploit, Technical Description, Third Party Advisory
• https://github.com/nextcloud/desktop/pull/5323Patch, Vendor Advisory
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-jh3g-wpwv-cqgrVendor Advisory
• https://ethz.ch/content/dam/ethz/special-interest/infk/inst-infsec/appliedcrypto/education/theses/report_DanieleCoppola.pdfExploit, Technical Description, Third Party Advisory
• https://github.com/nextcloud/desktop/pull/5323Patch, Vendor Advisory
• https://github.com/nextcloud/security-advisories/security/advisories/GHSA-jh3g-wpwv-cqgrVendor Advisory

Published

Apr 4, 2023

Last Modified

Jun 17, 2026

Status

Modified

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
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