Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.1.2, 9.0.6, and 8.2.9 suffer from SMB User Authentication Bypass
Published Mar 28, 2017
8.1
HIGHCVSS 3.0
EPSS 4.09%
Description
Nextcloud Server before 9.0.54 and 10.0.1 & ownCloud Server before 9.1.2, 9.0.6, and 8.2.9 suffer from SMB User Authentication Bypass. Nextcloud/ownCloud include an optional and not by default enabled SMB authentication component that allows authenticating users against an SMB server. This backend is implemented in a way that tries to connect to a SMB server and if that succeeded consider the user logged-in. The backend did not properly take into account SMB servers that have any kind of anonymous auth configured. This is the default on SMB servers nowadays and allows an unauthenticated attacker to gain access to an account without valid credentials. Note: The SMB backend is disabled by default and requires manual configuration in the Nextcloud/ownCloud config file. If you have not configured the SMB backend then you're not affected by this vulnerability.
Affected products
No data.
- < 9.0.54
- ≥ 10.0.0 · < 10.0.1
- ≥ 8.2.0 · < 8.2.9
- ≥ 9.0.0 · < 9.0.4
- ≥ 9.1.0 · < 9.1.2
No data.
No Red Hat product state for this CVE.
No package ranges for this CVE.
Remediation
No remediation recorded yet.
Metrics
No CVSS v4.0 score for this CVE.
No CVSS v3.1 score for this CVE.
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H
AV:N/AC:M/Au:N/C:P/I:P/A:P
This CVE is not in the KEV list.
No CISA SSVC assessment for this CVE yet.
Estimated probability of exploitation in the wild in the next 30 days (FIRST EPSS). As of Oct 1, 2026.
Score over time
2022–2026- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Percentile over time
- EPSS v2
- EPSS v3
- EPSS v4
- EPSS v5
Table of values (37 key points)
Flat stretches are collapsed; showing up to 120 newest points.
| Date | Score | Percentile | Model |
|---|---|---|---|
| Oct 1, 2026 | 4.09% (0.04095) | 90.42th | v5 (v2026.06.15) |
| Jun 15, 2026 | 4.09% (0.04095) | 89.39th | v5 (v2026.06.15) |
| Mar 4, 2026 | 3.86% (0.03864) | 87.99th | v4 (v2025.03.14) |
| Mar 1, 2026 | 5.57% (0.05570) | 90.17th | v4 (v2025.03.14) |
| Feb 4, 2026 | 3.86% (0.03864) | 87.92th | v4 (v2025.03.14) |
| Feb 1, 2026 | 5.57% (0.05570) | 90.11th | v4 (v2025.03.14) |
| Jan 4, 2026 | 3.86% (0.03864) | 87.86th | v4 (v2025.03.14) |
| Jan 1, 2026 | 5.57% (0.05570) | 90.07th | v4 (v2025.03.14) |
| Dec 4, 2025 | 3.86% (0.03864) | 87.79th | v4 (v2025.03.14) |
| Dec 1, 2025 | 5.57% (0.05570) | 89.99th | v4 (v2025.03.14) |
| Nov 4, 2025 | 3.86% (0.03864) | 87.72th | v4 (v2025.03.14) |
| Nov 1, 2025 | 5.57% (0.05570) | 89.90th | v4 (v2025.03.14) |
| Oct 4, 2025 | 3.86% (0.03864) | 87.74th | v4 (v2025.03.14) |
| Oct 1, 2025 | 5.57% (0.05570) | 89.93th | v4 (v2025.03.14) |
| Sep 4, 2025 | 3.86% (0.03864) | 87.78th | v4 (v2025.03.14) |
| Sep 1, 2025 | 5.57% (0.05570) | 89.99th | v4 (v2025.03.14) |
| Aug 4, 2025 | 3.86% (0.03864) | 87.79th | v4 (v2025.03.14) |
| Aug 1, 2025 | 5.57% (0.05570) | 89.98th | v4 (v2025.03.14) |
| Jul 5, 2025 | 3.86% (0.03864) | 87.72th | v4 (v2025.03.14) |
| Jul 1, 2025 | 5.57% (0.05570) | 89.88th | v4 (v2025.03.14) |
| Jun 8, 2025 | 3.86% (0.03864) | 87.67th | v4 (v2025.03.14) |
| Jun 1, 2025 | 5.57% (0.05570) | 89.84th | v4 (v2025.03.14) |
| May 5, 2025 | 3.86% (0.03864) | 87.58th | v4 (v2025.03.14) |
| May 1, 2025 | 5.57% (0.05570) | 89.79th | v4 (v2025.03.14) |
| Mar 30, 2025 | 3.86% (0.03864) | 87.14th | v4 (v2025.03.14) |
| Mar 29, 2025 | 8.30% (0.08305) | 86.84th | v4 (v2025.03.14) |
| Mar 28, 2025 | 3.86% (0.03864) | 87.16th | v4 (v2025.03.14) |
| Mar 27, 2025 | 5.57% (0.05570) | 88.90th | v4 (v2025.03.14) |
| Mar 18, 2025 | 4.51% (0.04509) | 88.44th | v4 (v2025.03.14) |
| Mar 17, 2025 | 7.46% (0.07458) | 91.11th | v4 (v2025.03.14) |
| Dec 12, 2024 | 0.39% (0.00394) | 74.26th | v3 (v2023.03.01) |
| Feb 8, 2024 | 0.31% (0.00308) | 69.10th | v3 (v2023.03.01) |
| Mar 7, 2023 | 0.31% (0.00308) | 65.15th | v3 (v2023.03.01) |
| Mar 6, 2023 | 1.54% (0.01537) | 74.52th | v2 (v2022.01.01) |
| Feb 23, 2023 | 1.54% (0.01537) | 74.48th | v2 (v2022.01.01) |
| Apr 1, 2022 | 1.54% (0.01537) | 72.41th | v2 (v2022.01.01) |
| Feb 4, 2022 | 1.54% (0.01537) | 51.33th | v2 (v2022.01.01) |
References (9)
- https://github.com/nextcloud/apps/commit/b85ace6840b8a6704641086bc3b8eb8e81cb2274 x_refsource_MISCIssue TrackingPatchThird Party Advisory
- https://github.com/nextcloud/apps/commit/decb91fd31f4ffab191cbf09ce4e5c55c67a4087 x_refsource_MISCIssue TrackingPatchThird Party Advisory
- https://github.com/owncloud/apps/commit/16cbccfc946c8711721fa684d78135ca1fb64791 x_refsource_MISCIssue TrackingPatchThird Party Advisory
- https://github.com/owncloud/apps/commit/5d47e7b52646cf79edadd78ce10c754290cbb732 x_refsource_MISCIssue TrackingPatchThird Party Advisory
- https://github.com/owncloud/apps/commit/a0e07b7ddd5a5fd850a6e07f8457d05b76a300b3 x_refsource_MISCIssue TrackingPatchThird Party Advisory
- https://hackerone.com/reports/148151 x_refsource_MISCExploitThird Party Advisory
- https://nextcloud.com/security/advisory/?id=nc-sa-2016-006 x_refsource_MISCPatchVendor Advisory
- https://owncloud.org/security/advisory/?id=oc-sa-2016-017 x_refsource_MISCPatchVendor Advisory
- https://rhinosecuritylabs.com/2016/10/operation-ownedcloud-exploitation-post-exploitation-persistence/ x_refsource_MISCExploitTechnical DescriptionThird Party Advisory
Change history (0)
No recorded changes yet.