by Kastro
Paper/Archive/CVE-2026-28198

CVE-2026-28198

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

EPSS 0.3%CVSS 9.4
critical.is priorityof 100
34
CVSS 9.4 (CNA)9.4 / 10 × 3028.2Not in CISA KEV+300.0EPSS percentile 27.5.275 × 205.5No public exploit+100.0SSVC exploitation: none+100.0
Description · from the CVE record

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.

Affected

ProductAffectedFixed inSource
NetBackup Flex OS< 6.46.4CNA

Scores by source

ENISA (CNA)9.4CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H
ENISA (CNA)8.8CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CISA ADPSSVCExploitation: none · Automatable: no · Technical impact: total

References

refcvcn.gov.it/cvcn/cve/CVE-2026-28198advisorygithub.com/cohesity/SecAdvisory/blob/master/COH-2026-0001.md