Auth bypass in Nextcloud Server
CVE-2023-49791
Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. In Nextcloud Server prior to versions 26.0.9 and 27.1.4; as well as Nextcloud Enterprise Server prior to versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4; when an attacker manages to get access to an active session of another user via another way, they could delete and modify workflows by sending calls directly to the API bypassing the password confirmation shown in the UI. Nextcloud Server versions 26.0.9 and 27.1.4 and Nextcloud Enterprise Server versions 23.0.12.13, 24.0.12.9, 25.0.13.4, 26.0.9, and 27.1.4 contain a patch for this issue. No known workarounds are available.
Published · last modified .
CVSS v3 metric
CVSS v3 base score 5.4 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:L.
EPSS exploit prediction
EPSS: 0.006 (47.0th percentile), scored .
Very low probability of exploitation in the next 30 days; routine patching cadence is appropriate. 47th percentile — 47.0% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.
EPSS over last 30 days · oldest: 0.006 · newest: 0.006 · change: 0.000
Affected products
- Nextcloud Server
- Nextcloud Security-Advisories — versions >= 23.0.0, < 23.0.12.13, >= 24.0.0, < 24.0.12.9, >= 25.0.0, < 25.0.13.4
Weakness classification (CWE)
References
- github.com/nextcloud/security-advisories/security/advisories/GHSA-3f8p-6qww-2prr (Vendor Advisory)
- github.com/nextcloud/server/pull/41520 (Patch)
- hackerone.com/reports/2120667 (Permissions Required)
Frequently asked questions
- What is CVE-2023-49791?
- CVE-2023-49791 is a medium-severity vulnerability in Nextcloud Server, classified under Improper Access Control. CVSS score: 5.4/10. Published 2023-12-22.
- How severe is CVE-2023-49791?
- Medium severity. CVSS v3 base score is 5.4 out of 10.