CVE-2026-45281
8.1 · HIGHOverview
CVE-2026-45281 is a high-severity vulnerability affecting nextcloud nextcloud_server. It was published on June 1, 2026 and has a CVSS 3.1 base score of 8.1 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
Nextcloud is an open source content collaboration platform. In Nextcloud Server from versions 32.0.0 to before 32.0.9, and 33.0.0 to before 33.0.3, with the knowledge of other users’ principal URL an attacker could possibly send a request to gain full access to their calendar. Therefore, the attacker must be an authenticated user. This is because of improper authorization controls in the backend of the calendar. If the attacker had access to the calendar, they would be able to view and modify it. It is recommended that the Nextcloud Server is upgraded to 33.0.3 or 32.0.9. It is recommended that the Nextcloud Enterprise Server is upgraded to 33.0.3, 32.0.9, 31.0.14.5, 30.0.17.9, 29.0.16.16, 28.0.14.17, 27.1.11.26, 26.0.13.26, 25.0.13.29, 24.0.12.34, 23.0.12.35, 22.2.10.39, or 21.0.9.23
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 | >= 32.0.0, < 32.0.9 | Affected |
Frequently Asked Questions
What is CVE-2026-45281?
CVE-2026-45281 is a high-severity vulnerability affecting nextcloud nextcloud_server. It was published on June 1, 2026 and has a CVSS 3.1 base score of 8.1 (HIGH).
How severe is CVE-2026-45281?
This vulnerability has a CVSS 3.1 base score of 8.1, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-45281?
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-2026-45281?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-45281 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
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