Vulnerability in Nextcloud Server
CVE-2021-32802
Nextcloud server is an open source, self hosted personal cloud. Nextcloud supports rendering image previews for user provided file content. For some image types, the Nextcloud server was invoking a third-party library that wasn't suited for untrusted user-supplied content. There are several security concerns with passing user-generated content to this library, such as Server-Side-Request-Forgery, file disclosure or potentially executing code on the system. The risk depends on your system configuration and the installed library version. It is recommended that the Nextcloud Server is upgraded to 20.0.12, 21.0.4 or 22.1.0. These versions do not use this library anymore. As a workaround users may disable previews by setting `enable_previews` to `false` in `config.php`.
EPSS: 0.026 (84.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 9.3 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:N/A:L.
Affected products
- Nextcloud Nextcloud_server
- Nextcloud Security-advisories — versions < 20.0.12, >= 21.0.0, < 21.0.4, >= 22.0.0, < 22.1.0
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Third Party Advisory, Mitigation)
- security-advisories@github.com (Permissions Required, Third Party Advisory, x_refsource_MISC)
- security-advisories@github.com (x_refsource_MISC, Vendor Advisory)
- security-advisories@github.com (vendor-advisory, Third Party Advisory, x_refsource_GENTOO)
Frequently asked questions
- What is CVE-2021-32802?
- CVE-2021-32802 is a critical-severity vulnerability in Nextcloud Server, classified under Inclusion of Functionality from Untrusted Control Sphere. CVSS score: 9.3/10. Published 2021-09-07.
- How severe is CVE-2021-32802?
- Critical severity. CVSS v3 base score is 9.3 out of 10.