A 2023 ownCloud flaw resurfaces and opens files with no credentials at all

CVE-2023-49105, a WebDAV authentication flaw rated CVSS 9.8 and fixed by ownCloud in late 2023, is now being actively exploited — CISA added it to the KEV catalog on 27 August 2026. Inventory your exposed ownCloud 10.x instances, move to 10.13.1 or later, and treat them as possible compromises.