CVE-2026-28197: Cohesity Netbackup Flex OS

High severity, CVSS 8.8. EPSS: 0.7% chance of exploitation in the next 30 days.

An authenticated, low-privileged user with access to the NetBackup Flex OS management shell could supply a specially crafted input to a privileged administrative command, causing it to execute arbitrary code with root-level permissions. Successful exploitation grants the attacker unrestricted control over the Flex appliance host and all hosted containers, fully compromising confidentiality, integrity, and availability.

Affected products

• Cohesity Netbackup Flex OS: before 6.4 (fixed in 6.4)

Published 2026-09-18. Last modified 2026-09-18.