Cyber Resilience

CVE-2026-16520

Published
21 August 2026
Modified
03 September 2026
CVSS Score v4 8.7
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N/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
EPSS Score 0.0039 32th percentile
Risk Priority 44 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2026-16520 is a high-severity Improper Input Validation (CWE-20) vulnerability in Genians Genian NAC (inferred from references). Its CVSS base score is 8.7 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Invalid Code Signature (T1036.001); ranked at the 32th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-23 (Data Mining Protection) and SA-11 (Developer Testing and Evaluation) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

Improper input validation and Exposure of sensitive information through data queries vulnerability in Genians Genian NAC V4.0, Genians Genian NAC V5.0, and Genians Genian ZTNA V6.0 allows SQL Injection and Authentication Bypass. This issue affects Genian NAC V4.0: from 4.0.0…

more

before 4.0.175(Revision 150340); Genian NAC V5.0: from 5.0.0 before 5.0.65 LTS(Revision 150331), from 5.0.0 before 5.0.75 LTS(Revision 150330), from 5.0.0 before 5.0.87 Release Stable(Revision 150329), and from 5.0.0 before 5.0.88(Revision 150328); Genian ZTNA V6.0: from 6.0.0 before 6.0.26 LTS(Revision 150337), from 6.0.0 before 6.0.35 LTS(Revision 150336), from 6.0.0 before 6.0.47 Release Stable(Revision 150334), and from 6.0.0 before 6.0.48(Revision 150333).

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1036.001 Invalid Code Signature Stealth
Adversaries may attempt to mimic features of valid code signatures to increase the chance of deceiving a user, analyst, or tool.
T1068 Exploitation for Privilege Escalation Privilege Escalation
Adversaries may exploit software vulnerabilities in an attempt to elevate privileges.
T1190 Exploit Public-Facing Application Initial Access
Adversaries may attempt to exploit a weakness in an Internet-facing host or system to initially access a network.
T1203 Exploitation for Client Execution Execution
Adversaries may exploit software vulnerabilities in client applications to execute code.
T1210 Exploitation of Remote Services Lateral Movement
Adversaries may exploit remote services to gain unauthorized access to internal systems once inside of a network.
T1213 Data from Information Repositories Collection
Adversaries may leverage information repositories to mine valuable information.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2024-51529Shared CWE-20
CVE-2026-0078Shared CWE-20
CVE-2026-11126Shared CWE-20
CVE-2025-66866Shared CWE-20
CVE-2026-21549Shared CWE-20
CVE-2023-43073Shared CWE-20
CVE-2025-15606Shared CWE-20
CVE-2026-17937Shared CWE-20
CVE-2026-11095Shared CWE-20
CVE-2023-40034Shared CWE-20

Affected Assets

Genians
Genian NAC
inferred from references and description; NVD did not file a CPE for this CVE

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

—

Mitigating Controls (NIST 800-53 r5) AI

AC-23 directly requires mechanisms to protect against unauthorized data mining and inference from statistical queries that would expose sensitive information.

Developer testing and evaluation can discover missing input validation through analysis or test cases.

SI-10 directly requires validity checks on information inputs, structurally preventing improper or missing validation.

Requiring documented development standards and tools can embed input-validation practices into the engineering process.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

DE.CM-03 partial match
prevents

Behavior analytics on query activity can detect inference attempts but does not prevent exposure at query time.

PR.AA-05 partial match
prevents

Least-privilege query permissions directly limit the data an attacker can request or infer.

PR.DS-10 partial match
prevents

Protecting data-in-use reduces what remains available for inference via queries.

PR.PS-06 partial match
prevents

Secure SDLC practices directly require and enforce input validation during development.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

mitigates

Classification helps identify sensitive data that must be protected from inference attacks.

prevents

Access control limits who can run queries that could expose sensitive information via inference.

prevents

Granular access rights reduce the ability of users to craft inference queries.

A.8.11 Data masking partial match
prevents

Data masking prevents inference by obscuring sensitive values returned in query results.

finds

DLP can detect and block queries or result sets that risk exposing sensitive information.

A.8.15 Logging partial match
finds

Logging query activity supports detection of inference attempts after the fact.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

RHEL 8 (1 rule)
  • V-230265 RHEL 8 must prevent the installation of software, patches, service packs, device drivers, or operating system components of local packages without verification they have been digitally signed using a certificate that is issued by a Certificate Authority (CA) that is recognized and approved by the organization. prevents CWE-20

References