Cyber Resilience

CVE-2026-3943

Command Injection

Published
11 March 2026
Modified
22 April 2026
CVSS Score v4 6.9
Click a component to see what it means
Raw vectorCVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:L/VI:L/VA:L/SC:N/SI:N/SA:N/E:P/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 0.39 98th percentile
Risk Priority 59 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-2026-3943 is a medium-severity Injection (CWE-74) vulnerability. Its CVSS base score is 6.9 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to SA-11 (Developer Testing and Evaluation) and SI-10 (Information Input Validation) — see the control section below for these in your framework.

Deeper analysis AI-assisted summary

Synthesised by an AI model from the NVD description and linked references — a reading aid, not an authoritative source.

CVE-2026-3943 is a command injection vulnerability (CWE-74, CWE-77) discovered in H3C ACG1000-AK230 devices up to version 20260227. The issue resides in an unknown component of the web interface endpoint /webui/?aaa_portal_auth_local_submit, where manipulation of the "suffix" argument enables arbitrary command execution. Published on 2026-03-11, it carries a CVSS v3.1 base score of 7.3 (AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L), indicating high severity due to its network accessibility and low complexity.

Remote attackers require no authentication, privileges, or user interaction to exploit this vulnerability over the network. Successful exploitation allows limited impacts on confidentiality, integrity, and availability, such as executing unauthorized commands on the device, potentially leading to data leakage, modification, or service disruption.

Advisories from VulDB and a related GitHub issue (leeyper/CVE #1) document the flaw, noting that the vendor is actively investigating and remediating it, though no specific patches are detailed in the available information. Security practitioners should monitor vendor updates via these sources.

The exploit has been publicly disclosed and could be weaponized, increasing the risk of real-world attacks on unpatched H3C ACG1000-AK230 devices.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A vulnerability was found in H3C ACG1000-AK230 up to 20260227. This affects an unknown part of the file /webui/?aaa_portal_auth_local_submit. The manipulation of the argument suffix results in command injection. The attack can be launched remotely. The exploit has been made…

more

public and could be used. The vendor is investigating and remediating this issue.

CWE(s)

Related Threats

MITRE ATT&CK Enterprise Techniques

T1059 Command and Scripting Interpreter Execution
Adversaries may abuse command and script interpreters to execute commands, scripts, or binaries.
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.
T1221 Template Injection Stealth
Adversaries may create or modify references in user document templates to conceal malicious code or force authentication attempts.
T1659 Content Injection Initial Access
Adversaries may gain access and continuously communicate with victims by injecting malicious content into systems through online network traffic.
T1674 Input Injection Execution
Adversaries may simulate keystrokes on a victim’s computer by various means to perform any type of action on behalf of the user, such as launching the command interpreter using keyboard shortcuts, typing an inline script to be executed,…
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2025-11331Shared CWE-74, CWE-77
CVE-2026-2163Shared CWE-74, CWE-77
CVE-2026-1624Shared CWE-74, CWE-77
CVE-2025-9581Shared CWE-74, CWE-77
CVE-2026-2530Shared CWE-74, CWE-77
CVE-2025-14108Shared CWE-74, CWE-77
CVE-2026-8210Shared CWE-74, CWE-77
CVE-2025-7524Shared CWE-74, CWE-77
CVE-2026-11448Shared CWE-74, CWE-77
CVE-2025-4850Shared CWE-74, CWE-77

Affected Assets

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)

—

Validate
Prove the fix (OWASP ASVS)
  • V1.2.1
  • V1.2.3
  • V1.2.5
  • V1.2.8

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover command-construction flaws before deployment.

SI-10 directly requires validation of information inputs to reject malformed or special-element content before it reaches downstream parsers.

Secure engineering principles include proper neutralization and safe command construction practices.

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.

PR.PS-06 mostly match
prevents

Secure SDLC practices directly require input validation and output encoding that prevent injection flaws.

DE.CM-09 partial match
prevents

Runtime monitoring of software and data can detect anomalous command execution resulting from injection.

ID.RA-01 partial match
prevents

Identifying recorded vulnerabilities enables remediation of command-injection flaws before exploitation.

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.

prevents

Secure coding standards require proper escaping and parameterization of commands, directly eliminating CWE-77.

finds

Security testing in development catches injection vulnerabilities before release.

A.8.15 Logging partial match
finds

Logging supports detection of injection attempts but does not prevent the weakness.

finds

Monitoring activities can identify active injection attacks after they occur.

prevents

Secure development life cycle mandates input validation and output encoding that directly prevent injection flaws.

prevents

Application security requirements explicitly call for controls against injection attacks in software design.

References