8.8High

Apache Cloudstack

CVE-2026-47359

Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection') vulnerability in Apache CloudStack's NAS backup provider plugin. The addBackupRepository API (available since 4.20.0.0) and updateBackupRepository API (introduced in 4.22.0.0) accept unsanitized command options for the backup repository. A malicious operator account can exploit this to inject arbitrary commands that execute on the KVM hypervisor host when any account subsequently performs a backup restore. This issue affects Apache CloudStack: from 4.20.0.0 through 4.20.3.0 and from 4.21.0.0 through 4.22.1.0. Users are recommended to upgrade to version 4.20.3.1 or 4.22.1.1 or later, which fixes the issue.

What this means for your business

  • It affects Apache Cloudstack. It matters if your company, or a supplier that handles your data, runs it.
  • An attacker can use it remotely, over a network, with an ordinary user login, and without anyone at your company clicking anything.
  • FIRST's prediction model gives it a 1% chance of attack attempts being seen in the next 30 days, ranking above 63% of all known flaws.

What to do

  1. 1Check whether your company or your suppliers run Apache Cloudstack, and which version. The affected versions are listed further down this page.
  2. 2If you do, apply the vendor's fix. A patch or vendor advisory has been published.

Not sure if your company is exposed?

Fastnexa’s certified penetration testers can check whether attackers could use this flaw, or others like it, against your websites, apps and network. The full test is free for our first 10 founding clients until 31 December 2026.

Scoring

CVSS
8.8 (v3.1)
Vector
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Weakness
CWE-78
Assigned by
security@apache.org

Dates

Published
2026-08-21
Last modified
2026-08-27
Sources
NVD

Affected products

  • Apache Cloudstack4.20.0.0 - 4.20.3.1, 4.21.0.0 - 4.22.1.1

As listed in the NVD configuration data. Not a statement about your estate.

References