Cyber Posture

CVE-2026-0641

MediumPublic PoC

Published: 06 January 2026

Published
06 January 2026
Modified
22 January 2026
KEV Added
Patch
CVSS Score 6.3 CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L
EPSS Score 0.0212 84.3th percentile
Risk Priority 14 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2026-0641 is a medium-severity Injection (CWE-74) vulnerability in Totolink Wa300 Firmware. Its CVSS base score is 6.3 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked in the top 15.7% 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 are NIST 800-53 SI-10 (Information Input Validation) and SI-2 (Flaw Remediation).

Threat & Defense at a Glance

What attackers do: exploitation maps to Exploit Public-Facing Application (T1190) and 1 other technique. What defenders deploy: see the NIST 800-53 controls recommended below.
Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

prevent

Directly mitigates command injection by requiring validation and sanitization of the UPLOAD_FILENAME argument in cstecgi.cgi to reject malicious payloads.

prevent

Addresses the specific flaw in sub_401510 by mandating identification, testing, and deployment of firmware patches or updates for the TOTOLINK WA300 router.

prevent

Limits the impact of arbitrary command execution from injected UPLOAD_FILENAME by enforcing least privilege on router processes and authenticated users.

MITRE ATT&CK Enterprise TechniquesAI

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.
T1059.004 Unix Shell Execution
Adversaries may abuse Unix shell commands and scripts for execution.
Why these techniques?

The vulnerability enables exploitation of a public-facing web application (T1190) via command injection in a CGI script, leading to arbitrary Unix shell command execution (T1059.004) on the router.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

A security vulnerability has been detected in TOTOLINK WA300 5.2cu.7112_B20190227. This vulnerability affects the function sub_401510 of the file cstecgi.cgi. The manipulation of the argument UPLOAD_FILENAME leads to command injection. The attack may be initiated remotely. The exploit has been…

more

disclosed publicly and may be used.

Deeper analysisAI

CVE-2026-0641 is a command injection vulnerability affecting the TOTOLINK WA300 router on firmware version 5.2cu.7112_B20190227. The issue resides in the sub_401510 function within the cstecgi.cgi file, where manipulation of the UPLOAD_FILENAME argument enables attackers to inject and execute arbitrary commands.

The vulnerability is exploitable remotely over the network with low complexity and no user interaction required, but it necessitates low privileges (PR:L) such as an authenticated user account. Exploitation yields limited impacts on confidentiality, integrity, and availability, as reflected in its CVSS v3.1 base score of 6.3 (AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L). Attackers can achieve remote code execution via the disclosed proof-of-concept.

Advisories on VulDB (ctiid.339684, id.339684) and a GitHub repository (https://github.com/JackWesleyy/CVE/blob/main/WA300/TOTOLINK_WA300_RCE.md, including PoC at #poc) detail the vulnerability and exploit, but no specific patches or vendor mitigations are referenced in the available information.

The exploit has been publicly disclosed and may be used, with associated CWEs CWE-74 and CWE-77 highlighting improper neutralization of special elements in commands.

Details

CWE(s)

Affected Products

totolink
wa300 firmware
5.2cu.7112_b20190227

CVEs Like This One

CVE-2026-4497Same product: Totolink Wa300
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CVE-2026-1327Same vendor: Totolink
CVE-2026-5104Same vendor: Totolink
CVE-2026-5177Same vendor: Totolink
CVE-2026-1547Same vendor: Totolink
CVE-2025-7952Same vendor: Totolink
CVE-2026-5102Same vendor: Totolink
CVE-2026-5103Same vendor: Totolink
CVE-2026-1149Same vendor: Totolink

References