Cyber Resilience

CVE-2023-27135

RCE in Totolink A7100Ru Firmware 7.4cu.2313_b20191024

Public PoCRCECommand Injection
Published
23 March 2023
Modified
25 February 2025
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 0.020 79th percentile
Risk Priority 87 floored blend · peak EPSS

Summary

CVE-2023-27135 is a critical-severity Command Injection (CWE-77) vulnerability in Totolink A7100Ru Firmware. Its CVSS base score is 9.8 (Critical).

Operationally, exploitation aligns with the MITRE ATT&CK technique Command and Scripting Interpreter (T1059); ranked in the top 21% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

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-2023-27135 is a command injection vulnerability in the TOTOLINK A7100RU wireless router running firmware version V7.4cu.2313_B20191024. The flaw resides in the web management interface at the endpoint /setting/setWanIeCfg, where the “enabled” parameter is processed without adequate sanitization, allowing arbitrary operating-system commands to be executed under the web-server process.

An unauthenticated attacker with network access can supply a crafted HTTP request containing shell metacharacters in the enabled field. Successful exploitation grants the attacker the ability to read, modify, or delete arbitrary files, create new accounts, or pivot further into attached networks, corresponding to the CVSS 9.8 rating that reflects no required credentials or user interaction.

Public references consist of proof-of-concept material hosted on GitHub that demonstrates the injection vector. No vendor advisory or firmware patch is referenced in the available sources.

The EPSS score for this CVE rose from a low baseline to a peak of 0.3113 on 2025-01-22 before receding to the current value of 0.0516, indicating a measurable increase in observed exploitation interest well after the original disclosure.

OWASP Top 10 for Web (2025)

A05:2025 Injection

EU & UK References

Vulnerability Data

TOTOlink A7100RU V7.4cu.2313_B20191024 was discovered to contain a command injection vulnerability via the enabled parameter at /setting/setWanIeCfg.

CWE(s)
CWE-77

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 →
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 →
T1059.003 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 →
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-2023-24238Same product: Totolink A7100Ru
CVE-2023-26978Same product: Totolink A7100Ru
CVE-2023-26848Same product: Totolink A7100Ru
CVE-2023-27232Same product: Totolink A7100Ru
CVE-2023-33556Same product: Totolink A7100Ru
CVE-2023-27229Same product: Totolink A7100Ru
CVE-2023-24236Same product: Totolink A7100Ru
CVE-2023-27231Same product: Totolink A7100Ru
CVE-2023-24184Same product: Totolink A7100Ru
CVE-2023-24276Same product: Totolink A7100Ru

Affected Assets

totolink
a7100ru firmware
7.4cu.2313_b20191024

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 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.

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