CVE-2021-32733
4.8 · MEDIUMOverview
CVE-2021-32733 is a medium-severity vulnerability affecting nextcloud nextcloud_server. It was published on July 12, 2021 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
Nextcloud Text is a collaborative document editing application that uses Markdown. A cross-site scripting vulnerability is present in versions prior to 19.0.13, 20.0.11, and 21.0.3. The Nextcloud Text application shipped with Nextcloud server used a `text/html` Content-Type when serving files to users. Due the strict Content-Security-Policy shipped with Nextcloud, this issue is not exploitable on modern browsers supporting Content-Security-Policy. The issue was fixed in versions 19.0.13, 20.0.11, and 21.0.3. As a workaround, use a browser that has support for Content-Security-Policy.
Remediation
Check the references section for vendor advisories and patches from nextcloud. Update nextcloud_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| nextcloud | nextcloud_server | >= 0, < 19.0.13 | Affected |
References
Frequently Asked Questions
What is CVE-2021-32733?
CVE-2021-32733 is a medium-severity vulnerability affecting nextcloud nextcloud_server. It was published on July 12, 2021 and has a CVSS 3.1 base score of 4.8 (MEDIUM).
How severe is CVE-2021-32733?
This vulnerability has a CVSS 3.1 base score of 4.8, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2021-32733?
Check the references section for vendor advisories and patches from nextcloud. Update nextcloud_server to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2021-32733?
CyberStrike's AI-powered security agents can automatically detect CVE-2021-32733 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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