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TI-2026-22537 Aliases CVE-2026-28198GHSA-h4hc-x5f6-wfc4

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

Priority MEDIUM 42CWE-347Published · Updated

Key facts

Attack vector
Network
Privileges required
Low
User interaction
None
Attack complexity
Low
Attack requirements
None
Impact type
Security bypass
Confidentiality · integrity · availability
High · High · High
Fix status
Fixed

Attack profile from CVSS 4.0 · CNA. Fix status from CNA. Impact type from CWE-347.

Summary

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.

Why it matters now

Exploitation None reported CISA SSVC · not in CISA KEV
EPSS 0.0034 27th percentileScored 2026-11-07
Fix Fixed NetBackup Flex OS (Cohesity): 6.4

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation
None
Automatable
No
Technical impact
Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

VendorProductAffected versionsFixed inStatusSource
CohesityNetBackup Flex OSbefore 6.46.4Patch availableCNA
  • NetBackup Flex OS VendorCohesity Affected before 6.4 Fixed in 6.4 Patch available CNA

Remediation

  • Fix · CNA NetBackup Flex OS (Cohesity) Fixed in 6.4

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    Cohesity NetBackup Flex OS — github.com/cohesity/SecAdvisory/blob/master/COH-2026-0001.md

    3 records Highest priority Priority MEDIUM 2 MEDIUM, 1 LOW

    Other records, highest priority first

    • TI-2026-22536 Privilege Escalation via Argument Injection in NetBackup Flex OS ShellPriority MEDIUM 44
    • TI-2026-22538 Sensitive File Disclosure via Relative Path Traversal in NetBackup Flex OS ShellPriority LOW 21
    Show all 3 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2026-28198
  2. 2026-10-03 Alias added: GHSA-h4hc-x5f6-wfc4

References

Advisory 1

Other 1

  • TI-2021-09357 Undocumented Default Cryptographic Key Vulnerability in Cohesity DataPlatform version 6.3… CVSS 3.1CRITICAL 9.8
  • TI-2026-22536 Privilege Escalation via Argument Injection in NetBackup Flex OS Shell CVSS 4.0CRITICAL 9.4
  • TI-2025-41479 Multiple authenticated OS command injection vulnerabilities exist in the Cohesity… CVSS 3.1HIGH 7.2
  • TI-2025-39485 Cohesity TranZman Migration Appliance Release 4.0 Build 14614 was discovered to contain… CVSS 3.1HIGH 7.2
  • TI-2025-39483 Incorrect access control in the component /opt/SRLtzm/bin/TapeDumper of Cohesity TranZman… CVSS 3.1HIGH 7.8
  • TI-2019-08412 A man-in-the-middle vulnerability related to vCenter access was found in Cohesity… CVSS 3.0HIGH 8.1
See all 13 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences