Cyber Resilience

CVE-2025-28035

RCE in Totolink A830R Firmware 4.1.2cu.5182_b20201102

Published
22 April 2025
Modified
17 June 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 0.012 66th percentile
Risk Priority 78 floored blend · peak EPSS

Summary

CVE-2025-28035 is a critical-severity OS Command Injection (CWE-78) vulnerability in Totolink A830R 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 34% 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.

TOTOLINK A830R routers running firmware version V4.1.2cu.5182_B20201102 contain a pre-authentication remote command execution flaw in the setNoticeCfg function. The vulnerability is triggered through the NoticeUrl parameter and is classified under CWE-78 as an instance of OS command injection. It carries a CVSS 3.1 score of 9.8, reflecting network-accessible exploitation without credentials or user interaction.

An unauthenticated attacker can send a crafted HTTP request to the affected device and execute arbitrary operating-system commands. Successful exploitation grants the attacker full control over the router, including the ability to read or modify configuration data, intercept traffic, or pivot into the local network.

Public references consist of researcher notes hosted on Notion that describe the issue but do not include vendor advisories, firmware updates, or mitigation guidance. The EPSS score rose from lower values after disclosure to a peak of 0.0636 on 2026-02-16 before receding to the current 0.0374, indicating a temporary increase in exploitation interest.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

TOTOLINK A830R V4.1.2cu.5182_B20201102 was found to contain a pre-auth remote command execution vulnerability in the setNoticeCfg function through the NoticeUrl parameter.

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-2025-28034Same product: Totolink A3000Ru
CVE-2025-28036Same product: Totolink A3000Ru
CVE-2025-28037Same product: Totolink A810R
CVE-2025-28138Same product: Totolink A800R
CVE-2025-28256Same product: Totolink A3100R
CVE-2025-28137Same product: Totolink A810R
CVE-2022-25075Same product: Totolink A3000Ru
CVE-2025-28032Same product: Totolink A3000Ru
CVE-2025-28033Same product: Totolink A3000Ru
CVE-2024-0292Same vendor: Totolink

Affected Assets

totolink
a830r firmware
4.1.2cu.5182_b20201102
totolink
a3100r firmware
4.1.2cu.5247_b20211129
totolink
a810r firmware
4.1.2cu.5182_b20201026
totolink
a800r firmware
4.1.2cu.5137_b20200730
totolink
a3000ru firmware
5.9c.5185_b20201128
totolink
a950rg firmware
4.1.2cu.5161_b20200903

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