CVE-2026-21666
9.9 · CRITICALOverview
CVE-2026-21666 is a critical-severity vulnerability affecting veeam veeam_backup_\&_replication. It was published on March 12, 2026 and has a CVSS 3.1 base score of 9.9 (CRITICAL).
This vulnerability has a CVSS 3.1 base score of 9.9, rated CRITICAL. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
A vulnerability allowing an authenticated domain user to perform remote code execution (RCE) on the Backup Server.
Remediation
Check the references section for vendor advisories and patches from veeam. Update veeam_backup_\&_replication 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 |
|---|---|---|---|
| veeam | veeam_backup_\&_replication | >= 12.0.0.1402, < 12.3.2.4465 | Affected |
References
Frequently Asked Questions
What is CVE-2026-21666?
CVE-2026-21666 is a critical-severity vulnerability affecting veeam veeam_backup_\&_replication. It was published on March 12, 2026 and has a CVSS 3.1 base score of 9.9 (CRITICAL).
How severe is CVE-2026-21666?
This vulnerability has a CVSS 3.1 base score of 9.9, rated CRITICAL. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-21666?
Check the references section for vendor advisories and patches from veeam. Update veeam_backup_\&_replication 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-2026-21666?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-21666 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.
Automated penetration testing that runs continuously, not just quarterly.
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