Privilege Escalation via Argument Injection in NetBackup Flex OS Shell

published 2026-09-18 52 d ago modified 2026-09-18 51 d ago also EUVD-2026-82874

cvss: 8.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 0.7%; EPSS 0.7% chance of exploitation in 30 days, percentile 52%
public exploits: 0; none known

An authenticated, low-privileged user with access to the NetBackup Flex OS management shell could supply a specially crafted input to a privileged administrative command, causing it to execute arbitrary code with root-level permissions. Successful exploitation grants the attacker unrestricted control over the Flex appliance host and all hosted containers, fully compromising confidentiality, integrity, and availability.

Patch / fix

fixed in 1

Cohesity NetBackup Flex OS 6.4

CISA SSVC

Exploitation: none
Automatable: no
Technical impact: total
Assessed: 51 d ago (2026-09-18)

Exploit prediction

0.67% chance of exploitation in the next 30 days, higher than 52% of all scored CVEs (FIRST EPSS, 2026-11-08).

CVSS scores

assigned by	version	score	vector
CNA	4.0	9.4	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
CNA	3.1	8.8	CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
CNA	4.0	9.4	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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Affected products

Cohesity NetBackup Flex OS

Classification

Weakness

CWE-88 Improper Neutralization of Argument Delimiters in a Command

References

github.com /cohesity/SecAdvisory/blob/master/COH-2026-0001.md
vendor-advisory
cvcn.gov.it /cvcn/cve/CVE-2026-28197
government-resource

Sources

CVE List CVE-2026-28197
NVD CVE-2026-28197

Fencer Vulns keeps one entry per vulnerability: the CVE id wins, then GHSA, and records that alias each other are merged, except that two CVEs always keep separate entries. The same data is available as JSON.

Summary