CVE-2023-40253· NVD / CVE Program· CNA krcert

Improper Authentication vulnerability in Genians Genian NAC V4.0, Genians Genian NAC V5.0, Genians Genian NAC Suite V5.0, Genians Genian ZTN

Noroxi assessment

Priority: Monitor (action score 39/100)

The sources we track (CISA KEV, Exploit-DB, Metasploit, Nuclei, GitHub) show no public exploit code or exploitation in the wild.
Probability of exploitation in the next 30 days: 0.41% (FIRST EPSS).
Anyone who can reach it over the internet can trigger it. No account or password is required. No user action is required. No special conditions are required; it is repeatable.
Fixed version: Genians Genian NAC Suite V5.0 V5.0.55; Genians Genian NAC V4.0 V4.0.156; Genians Genian NAC V5.0 V5.0.42 (Revision 117461).
Severity is disputed: the assigning authority (CNA) scores it 6.0, NVD 9.8.

Low priority for now. Upgrade to Genians Genian NAC Suite V5.0 V5.0.55; Genians Genian NAC V4.0 V4.0.156; Genians Genian NAC V5.0 V5.0.42 (Revision 117461) or later.

Generated automatically from the record's data: CVSS (NVD and CNA), CISA KEV and SSVC, FIRST EPSS, exploit sources, fixed versions. How we calculate it

Primary sources: NVD · CVE.org · FIRST EPSS

Improper Authentication vulnerability in Genians Genian NAC V4.0, Genians Genian NAC V5.0, Genians Genian NAC Suite V5.0, Genians Genian ZTNA allows Authentication Abuse.This issue affects Genian NAC V4.0: from V4.0.0 through V4.0.155; Genian NAC V5.0: from V5.0.0 through V5.0.42 (Revision 117460); Genian NAC Suite V5.0: from V5.0.0 through V5.0.54; Genian ZTNA: from V6.0.0 through V6.0.15.

CriticalCVSS 9.8 · v3.1—No exploit Fix available

Published: Aug 11, 2023
Updated: Jun 17, 2026
EPSS: 0.4% · 34th percentile
CWE: CWE-78

Report tools

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Action score

Monitor

Low priority for now.

CVSS: 39 / 40 · 9.8 / 10
CISA KEV: 0 / 30 · Not listed
EPSS: 0 / 30 · 0.4%

CISA SSVC decision

Exploitation: none
Automatable: no
Technical impact: partial

Vulnrichment: CISA's decision-tree inputs.

CNA vs NVD score

NVD: 9.8
CNA · krcert: 6.0; 3.8 point gap

CVSS:3.1/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:H/A:N

The score given by the assigning authority versus NVD’s independent score. A gap means the severity is contested.

Get told when this record changes

Not in KEV: no record of exploitation in the wild
No public exploit code on record
A fix has been released

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Noroxi analysis

What does it mean in your environment?

The assessment above is generated automatically from the record's data; it doesn't know your environment. Our team verifies on your systems whether this vulnerability is actually exploitable and which mitigation is enough.

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Affected systems

Is your version affected?

Pick the product and type the version you run. It's compared with this record's version ranges in your browser; the version isn't sent anywhere.

Vendor	Product	CPE
genians	genian nac	cpe:2.3:a:genians:genian_nac
genians	genian ztna	cpe:2.3:a:genians:genian_ztna

Affected versions

NVD version ranges (for catalog products). Add the product to your stack with a version and matching uses these.

genians genian nac4.0.0 and later · before 4.0.156
genians genian nac5.0.0 and later · before 5.0.55
genians genian nac5.0.42
genians genian ztna6.0.0 and later · before 6.0.16

Versions reported by the vendor

Affected version ranges reported by the assigning authority (krcert). Independent of NVD's CPE analysis and usually ahead of it.

Genians Genian NAC Suite V5.0
- V5.0.0 and later · up to and including V5.0.54affectedfixed in V5.0.55
Genians Genian NAC V4.0
- V4.0.0 and later · up to and including V4.0.155affectedfixed in V4.0.156
Genians Genian NAC V5.0
- V5.0.0 and later · up to and including V5.0.42 (Revision 117460)affectedfixed in V5.0.42 (Revision 117461)
Genians Genian ZTNA
- V6.0.0 and later · up to and including V6.0.15affectedfixed in V6.0.16

Same product

genians: all records

Other highest-scoring records for the same primary product.

CVE-2021-26622Genian NAC remote code execution vulnerability
41Plan
CVE-2023-40252Improper Control of Generation of Code ('Code Injection') vulnerability in Genians Genian NAC V4.0, Genians Genian NAC V5.0, Genians Genian
39Monitor
CVE-2023-40254Download of Code Without Integrity Check vulnerability in Genians Genian NAC V4.0, Genians Genian NAC V5.0, Genians Genian NAC Suite V5.0, G
39Monitor

Published before and after this one in the same product

Later →CVE-2023-40251Aug 17, 2023 · Missing Encryption of Sensitive Data vulnerability in Genians Genian NAC V4.0, Genians Genian NAC V5.0, Genians Genian NAC Suite V5.0, Genia
23Monitor

Remediation

Which version to upgrade to

Fix versions compiled from the vendor, package registries and Microsoft. Verify the vendor's note before upgrading.

Product / package	Fixed version	Source
Genians Genian NAC Suite V5.0	V5.0.55	Vendor (CNA)
Genians Genian NAC V4.0	V4.0.156	Vendor (CNA)
Genians Genian NAC V5.0	V5.0.42 (Revision 117461)	Vendor (CNA)
Genians Genian ZTNA	V6.0.16	Vendor (CNA)

Exploit status

No known public exploit

No public exploit has been observed yet. That doesn't mean you're safe, only that the bar is a little higher.

Research context

For pentesters and researchers: attack profile, score disagreement, timeline, patch commits, credits, variant and chain candidates, bug bounty scope. All derived from existing data; no exploit code.

Timeline

From publication to today: proof of concept, Metasploit module, CISA KEV and fix record. Dates are as reported by the sources.

No dated events beyond publication.

EPSS, last 120 days

FIRST EPSS daily score; only changes of 0.01 or more are recorded (step chart).

Patch and commit links

Commit, PR and diff links among the references. A starting point for patch-diffing and variant hunting; fixes, not exploits.

No commit or PR link among the references.

Credits

All researchers

Finders, reporters and analysts named in the CNA record. Click a name for that researcher’s other records.

No credits in the CNA record.

Variant candidates

Same product, same weakness class, within 18 months. If the patch missed the root cause, the sibling bug is here.

No nightly-computed relations.

Chain candidates

An authentication bypass and a privilege-requiring bug in the same product, published close together: combined they may become an unauthenticated path.

—

Bug bounty scope

No known public program.

Source: bounty-targets-data (public HackerOne, Bugcrowd, Intigriti, YesWeHack listings).

Technical details

Attack conditions

Anyone who can reach it over the internet can trigger it.
No account or password is required.
No user action is required.
No special conditions are required; it is repeatable.

If successful

Confidentiality: high · data can be read
Integrity: high · data or configuration can be modified
Availability: high · the service can be disrupted

Attack vector: Network
Attack complexity: Low
Privileges required: None
User interaction: None
Scope: Unchanged
Confidentiality impact: High
Integrity impact: High
Availability impact: High

Weakness class (CWE)

CWE-78 · Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

nvd-primary

Root cause

User input is inserted as text into a shell command. The shell may interpret special characters in the input as part of the command.

The bug in code

The whole CWE-78 class

A representative example of this vulnerability class. Not the vendor's source code; it shows the faulty pattern and its fix.

Vulnerable

1const host = req.body.host;
2exec("ping -c 1 " + host, onResult);

Fixed

1const host = req.body.host;
2if (!/^[a-z0-9.-]{1,253}$/i.test(host)) return res.sendStatus(400);
3execFile("ping", ["-c", "1", host], onResult);

Attack context

MITRE CAPEC attack patterns and ATT&CK techniques for this weakness class (CWE). A starting point for detection rules and threat hunting.

Attack patterns (CAPEC)

ATT&CK techniques

—

Change log

Fix✗ → ✓Sep 28, 2026, 10:08 PM UTC

For records you follow, these changes also arrive as notifications. →

References

docs.genians.com/nac/5.0/release/ko/advisories/GN-SA-2023-001.html

Vendor advisories and official records. Exploit/PoC links are deliberately left out.

All records