CVE-2026-28199: Sensitive File Disclosure via Relative Path Traversal in NetBackup Flex OS Shell

Severity: low (CVSS 3.3 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-09-18 · updated 2026-09-18
Weakness: CWE-347

Description

An authenticated user with access to the NetBackup Flex OS management shell could read arbitrary files from the underlying operating system by supplying a specially crafted path argument to a diagnostic command. Successful exploitation could expose sensitive system configuration and credential material stored on the appliance.

Affected products

Cohesity NetBackup Flex OS: before 6.4 — fixed in 6.4

How to fix

Upgrade to a fixed version: Cohesity NetBackup Flex OS 6.4. Check the vendor advisory for mitigations.

References

https://github.com/cohesity/SecAdvisory/blob/master/COH-2026-0001.md
https://www.cvcn.gov.it/cvcn/cve/CVE-2026-28199

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