CVE-2026-28198
Privilege Escalation via Cryptographic Signature Verification Bypass in NetBackup Flex OS Shell
Description
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.
INFO
Published Date :
Sept. 18, 2026, 12:17 p.m.
Last Modified :
Sept. 18, 2026, 12:17 p.m.
Remotely Exploit :
Yes !
Source :
a6d3dc9e-0591-4a13-bce7-0f5b31ff6158
Affected Products
The following products are affected by CVE-2026-28198
vulnerability.
Even if cvefeed.io is aware of the exact versions of the
products
that
are
affected, the information is not represented in the table below.
No affected product recoded yet
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS 3.1 | HIGH | a6d3dc9e-0591-4a13-bce7-0f5b31ff6158 | ||||
| CVSS 4.0 | CRITICAL | a6d3dc9e-0591-4a13-bce7-0f5b31ff6158 | ||||
| CVSS 4.0 | CRITICAL | a6d3dc9e-0591-4a13-bce7-0f5b31ff6158 |
Solution
- Apply security updates for NetBackup Flex OS.
- Review and enforce access controls.
- Restrict shell access for low-privileged users.
- Monitor for unauthorized access attempts.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-28198.
| URL | Resource |
|---|---|
| https://github.com/cohesity/SecAdvisory/blob/master/COH-2026-0001.md | |
| https://www.cvcn.gov.it/cvcn/cve/CVE-2026-28198 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-28198 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-28198
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-28198 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-28198 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
New CVE Received by a6d3dc9e-0591-4a13-bce7-0f5b31ff6158
Sep. 18, 2026
Action Type Old Value New Value Added Description 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. Added CVSS V4.0 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 Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H Added CWE CWE-347 Added Affected New affected value received. <a href="https://github.com/CVEProject/cvelistV5/blob/main/cves/2026/28xxx/CVE-2026-28198.json">CVE-2026-28198</a> Added Reference https://github.com/cohesity/SecAdvisory/blob/master/COH-2026-0001.md Added Reference https://www.cvcn.gov.it/cvcn/cve/CVE-2026-28198