CVE-2021-32802
No exploitation reported by the sources we read.
- Published2021-09-07
- Fixed in22.1.0 · 21.0.4 · 20.0.12
- WeaknessCWE-829
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
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`.
Timeline
dates in UTC- 2021-09-0722:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 21:37 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-32802?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-32802?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 22.x | ≥ 22.0.0, < 22.1.0 | 22.1.0 | NVD |
| 21.0 | ≥ 21.0.0, < 21.0.4 | 21.0.4 | NVD |
| 20.0 | < 20.0.12 | 20.0.12 | NVD |
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
- Update Nextcloud nextcloud server to 22.1.0 · 21.0.4 · 20.0.12
Advisories and patches
- docs.nextcloud.comVendor Advisory
- github.comMitigation
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- 2021-09-07
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-32802?
Is CVE-2021-32802 actively exploited?
What is the CVSS score for CVE-2021-32802?
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Related vulnerabilities
Same product first, then the same vendor advisory and the same publication week.