Cyber Resilience

CVE-2026-31178

RCE in Totolink A3300R Firmware 17.0.0cu.557_b20221024

Published
23 April 2026
Modified
27 April 2026
CVSS Score v3.1 9.8
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
EPSS Score 0.0058 45th percentile
Risk Priority 72 floored blend · peak EPSS

Summary

CVE-2026-31178 is a critical-severity OS Command Injection (CWE-78) vulnerability in Totolink A3300R Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked at the 45th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

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-2026-31178 is a command injection vulnerability (CWE-78) discovered in the TOTOLINK A3300R firmware version v17.0.0cu.557_B20221024. The issue resides in the /cgi-bin/cstecgi.cgi endpoint, where the stunMaxAlive parameter fails to properly sanitize user input, enabling attackers to inject and execute arbitrary operating system commands.

The vulnerability carries a CVSS v3.1 base score of 9.8 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H), indicating critical severity due to its network accessibility, low attack complexity, lack of required privileges or user interaction, and high impact across confidentiality, integrity, and availability. Remote, unauthenticated attackers can exploit it by sending a malicious HTTP request to the affected endpoint, achieving arbitrary command execution on the router with the privileges of the web server process.

Proof-of-concept exploit code demonstrating the command injection is publicly available in the GitHub repository https://github.com/Svigo-o/TOTOLINK-Vul/tree/main/totolink-a3300r-stun-max-alive-cmd-injection. No vendor advisories, patches, or specific mitigation guidance are detailed in the provided references.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

An issue was discovered in ToToLink A3300R firmware v17.0.0cu.557_B20221024 allowing attackers to execute arbitrary commands via the stunMaxAlive parameter to /cgi-bin/cstecgi.cgi.

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.
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
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.
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-37172Same product: Totolink A3300R
CVE-2024-24328Same product: Totolink A3300R
CVE-2024-23059Same product: Totolink A3300R
CVE-2024-24330Same product: Totolink A3300R
CVE-2023-37173Same product: Totolink A3300R
CVE-2024-24331Same product: Totolink A3300R
CVE-2024-24326Same product: Totolink A3300R
CVE-2023-37170Same product: Totolink A3300R
CVE-2024-22942Same product: Totolink A3300R
CVE-2024-24329Same product: Totolink A3300R

Affected Assets

totolink
a3300r firmware
17.0.0cu.557_b20221024

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)
  • V1.2.5
  • V1.2.8
  • V15.2.5

Mitigating Controls (NIST 800-53 r5) AI

Developer testing and evaluation can discover missing or incorrect command sanitization during development.

Input validation directly neutralizes or rejects special characters that would otherwise alter OS command structure.

Least privilege reduces the permissions available to any process that could be subverted by injected commands.

Least functionality restricts available OS commands and interpreters, limiting the blast radius of injection.

Secure engineering principles require proper neutralization of untrusted input before command construction.

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

PR.PS-06's SDLC practices directly require secure coding and input handling that blocks command-injection defects, yet the single broad outcome leaves many specific neutralization vectors and verification gaps unaddressed.

PR.PS-02 partial match
prevents

Routine patching/maintenance can remediate known command-injection CVEs in dependencies (partial forward) but does nothing to stop developers from introducing improper neutralization in custom code (none reverse).

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.

finds

Security testing and code review target insecure use of operating-system command interfaces, catching command-injection flaws introduced during development.

References