CVE-2026-28198criticalCWE-347

CVE-2026-28198: critical vulnerability in Cohesity NetBackup Flex OS

Privilege Escalation via Cryptographic Signature Verification Bypass in NetBackup Flex OS Shell

Published

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28Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 9.4epss 0.3%
An authenticated, low-privileged user with access to the NetBackup Flex OS management shell could bypass the cryptographic signature verification step of a privileged support command by supplying a specially formed access credential. Successful exploitation grants the attacker an unrestricted root shell with full control over the Flex appliance host and all hosted containers, completely compromising confidentiality, integrity, and availability.
CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
Affected products
Cohesity · NetBackup Flex OS
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CVE-2026-28197CRITICALPrivilege Escalation via Argument Injection in NetBackup Flex OS ShellEPSS 0.7%CVE-2026-28199MEDIUMSensitive File Disclosure via Relative Path Traversal in NetBackup Flex OS ShellEPSS 0.1%