Cyber Resilience

CVE-2026-3301

RCE in Totolink N300Rh Firmware 6.1c.1349_b20181018 … 6.1c.1353_b20190305

Public PoCRCECommand Injection
Published
27 February 2026
Modified
27 February 2026
Patch / advisory
View advisory
CVSS Score v4 8.9
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:H/VA:H/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 0.040 90th percentile
Risk Priority 50 floored blend · peak EPSS

Summary

CVE-2026-3301 is a high-severity Command Injection (CWE-77) vulnerability in Totolink N300Rh Firmware. Its CVSS base score is 8.9 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 10% of CVEs by exploit likelihood; 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-2026-3301 is an OS command injection vulnerability (CWE-77, CWE-78) affecting the Totolink N300RH router on firmware version 6.1c.1353_B20190305. The flaw resides in the setWebWlanIdx function within the /cgi-bin/cstecgi.cgi file of the Web Management Interface. Manipulation of the webWlanIdx argument enables arbitrary OS command execution.

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. Remote attackers require no authentication, privileges, or user interaction to exploit it over the network with low complexity. Successful exploitation allows full remote code execution, compromising confidentiality, integrity, and availability of the affected device.

Advisories from VulDB (ctiid.348052, id.348052, submit.761297) document the issue, while a public proof-of-concept exploit for RCE is available on GitHub at xyh4ck/iot_poc. The Totolink vendor website provides a reference point for potential firmware updates or mitigation guidance.

A publicly released exploit increases the likelihood of real-world attacks against unpatched Totolink N300RH devices.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

A security flaw has been discovered in Totolink N300RH 6.1c.1353_B20190305. Affected by this vulnerability is the function setWebWlanIdx of the file /cgi-bin/cstecgi.cgi of the component Web Management Interface. Performing a manipulation of the argument webWlanIdx results in os command injection.…

more

The attack can be initiated remotely. The exploit has been released to the public and may be used for attacks.

CWE(s)
CWE-77CWE-78

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.
attack.mitre.org →
T1059.003 Windows Command Shell Execution
Adversaries may abuse the Windows command shell for execution.
attack.mitre.org →
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
attack.mitre.org →
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.
attack.mitre.org →
T1059.001 PowerShell Execution
Adversaries may abuse PowerShell commands and scripts for execution.
attack.mitre.org →
T1059.008 Network Device CLI Execution
Adversaries may abuse scripting or built-in command line interpreters (CLI) on network devices to execute malicious command and payloads.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2026-3696Same product: Totolink N300Rh
CVE-2025-4849Same product: Totolink N300Rh
CVE-2025-4850Same product: Totolink N300Rh
CVE-2025-4851Same product: Totolink N300Rh
CVE-2025-2095Same vendor: Totolink
CVE-2024-10966Same vendor: Totolink
CVE-2025-2094Same vendor: Totolink
CVE-2025-6619Same vendor: Totolink
CVE-2025-1339Same vendor: Totolink
CVE-2025-14586Same vendor: Totolink

Affected Assets

totolink
n300rh firmware
6.1c.1349_b20181018, 6.1c.1353_b20190305

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)
  • V1.2.3
  • V1.2.5
  • V1.2.8
  • V1.2.9

Mitigating Controls (NIST 800-53 r5) AI

SA-11 Developer Testing and Evaluation good match

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

SI-10 Information Input Validation good match

Input validation directly stops construction of commands from untrusted data containing special elements.

AC-6 Least Privilege partial match

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

CM-7 Least Functionality partial match

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

SA-8 Security and Privacy Engineering Principles partial match

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 neutralization that prevent command injection.

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.

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.

A.8.28 Secure coding mostly match
prevents

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

A.8.29 Security testing in development and acceptance mostly match
finds

Security testing in development catches command-injection vulnerabilities before release.

A.8.25 Secure development life cycle partial match
prevents

Secure development life cycle mandates input validation and command construction practices that directly prevent command injection.

A.8.26 Application security requirements partial match
prevents

Application security requirements explicitly call for controls against injection flaws including command injection.

A.8.27 Secure system architecture and engineering principles partial match
prevents

Secure architecture principles reduce the attack surface but do not prescribe the specific neutralization techniques needed.

A.8.31 Separation of development, test and production environments none match
none

Environment separation limits the blast radius of an exploited command injection but does not prevent the flaw itself.

References