CVE-2026-21667Network attack vector

Authenticated remote code execution on Backup Server

Published Mar 12, 2026 · Updated Mar 12, 2026

Remote code execution in Veeam Backup & Replication 12.3.2.4165 and earlier allows remote authenticated users to execute code on the Backup Server. Veeam has not published the affected component, vulnerable operation, or attacker-controlled input that triggers the flaw. Exploitation requires credentials for a domain user and can compromise the Backup Server's confidentiality, integrity, and availability.

CVSS severity9.9
Critical
EPSS probability1.13%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Remote code execution in Veeam Backup & Replication 12.3.2.4165 and earlier allows remote authenticated users to execute code on the Backup Server. Veeam has not published the affected component, vulnerable operation, or attacker-controlled input that triggers the flaw. Exploitation requires credentials for a domain user and can compromise the Backup Server's confidentiality, integrity, and availability.

The record

CVE
CVE-2026-21667
Published
Mar 12, 2026
Updated
Mar 12, 2026
Vendor
Veeam Software
Product
Veeam Backup & Replication
Classifications
CWE-284, T1210
Attack vector
network
Privileges
authenticated

Timeline

How it unfolded

  1. Mar 12, 2026CVE publishedPublication date reported by the CVE source.
  2. Mar 12, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

Compare your product and version with the public record. A matching version still requires validation against your environment.

Is a vulnerable build present?

Affected versions are unavailable in this record. Check the vendor advisory for version and patch details.

What conditions does exploitation require?

Attack vectornetwork
Required privilegesauthenticated

What is affected?

Veeam Software · Veeam Backup & ReplicationAffected versions are unavailable in this record.

Published CVSS scores

8.8NIST NVDCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
9.9VeeamCVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

Daily unique IPsNo honeypot observations are available for this CVE in the selected window.

No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectornetwork
Privilegesauthenticated
Known exploitationUnconfirmed
Public exploitUnconfirmed

Weakness, pattern, technique

CWE-284Improper Access Control
T1210Exploitation of Remote Services

Public exploit references

No public exploit references are available in this record.

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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