CVE-2023-39962 json
Users can delete external storage mount points
published 2023-08-10 3 y ago modified 2026-06-17 4 mo ago also EUVD-2023-43659
- cvss
- 7.7
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 1.0%
- EPSS 1.0% chance of exploitation in 30 days, percentile 63%
- public exploits
- 0
- none known
Summary
Nextcloud Server provides data storage for Nextcloud, an open source cloud platform. Starting in version 19.0.0 and prior to versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.8, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1, a malicious user could delete any personal or global external storage, making them inaccessible for everyone else as well. Nextcloud server versions 25.0.9, 26.0.4, and 27.0.1 and Nextcloud Enterprise Server versions 19.0.13.10, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, and 27.0.1 contain a patch for this issue. As a workaround, disable app files_external. This also makes the external storage inaccessible but retains the configurations until a patched version has been deployed.
Patch / fix
- nextcloud server 19.0.13.0, 20.0.14.15, 21.0.9.13, 22.2.10.14, 23.0.12.9, 24.0.12.5, 25.0.9, 26.0.4, 27.0.1
- github.com/nextcloud/server#39323 pull request
CISA SSVC
- Exploitation
- Proof of concept is public
- Automatable
- no
- Technical impact
- partial
- Assessed
- 2 y ago
Exploit prediction
1.02% chance of exploitation in the next 30 days, higher than 63% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 7.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
| NVD | 3.1 | 7.7 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:N/I:N/A:H |
Affected products
- nextcloud security-advisories
- nextcloud server
Classification
- Weakness
-
- CWE-284 Improper Access Control
References
-
github.com
/nextcloud/server/pull/39323
patch
-
github.com
/nextcloud/security-advisories/security/advisories/GHSA-xwxx-2752-w3xm
vendor-advisory
-
hackerone.com
/reports/2047168
third-party-advisory
Sources
- CVE List CVE-2023-39962
- NVD CVE-2023-39962
Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.