# CVE-2026-28198

Authenticated low-privileged user can bypass signature checks to gain root on NetBackup Flex OS.

- Page: https://www.vulneraibility.com/cve/CVE-2026-28198
- CVSS: 9.4
- Known exploited: not in CISA KEV as of our last sync
- EPSS: 0.34% (percentile 27.5)
- CISA SSVC: exploitation none, automatable no, technical impact total (assessed 2026-09-18)
- Weakness: CWE-347
- Published: 2026-09-18

## Affected versions

- Cohesity NetBackup Flex OS: affected < 6.4

A version outside these ranges is not a statement that it is unaffected.

## Impact

Authenticated local user can bypass cryptographic verification to obtain an unrestricted root shell, compromising host and all containers.

## Action

Immediate action required

## Recommendation

Restrict/monitor management shell access, rotate credentials, isolate appliances; apply vendor patch when available.

## References

- [other] https://www.cvcn.gov.it/cvcn/cve/CVE-2026-28198
- [advisory] https://github.com/cohesity/SecAdvisory/blob/master/COH-2026-0001.md

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Summary, impact and action are written by the vulneraibility.com AI analysis pipeline from the CVE record, NVD, CISA and FIRST data; verify against the references.