CVE-2026-51731
Deferred Deferred - Pending Action

Incorrect Access Control in TOTOLINK T6 Firmware

Publication date: 2026-08-31

Last updated on: 2026-08-31

Assigner: MITRE

Description
Incorrect access control in the delVlanCfg function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to remove VLAN entries via sending a crafted POST request to /cgi-bin/cstecgi.cgi.

CVSS Scores

EPSS Scores

Probability:
Percentile:

Meta Information

Published
2026-08-31
Last Modified
2026-08-31
Generated
2026-09-01
AI Q&A
2026-08-31
EPSS Evaluated
N/A
NVD
CVE-2026-51731
EUVD
EUVD-2026-68755

Affected Vendors & Products

Showing 1 associated CPE
Vendor Product Version / Range
totolink t6 4.1.5cu.748_b20211015

Helpful Resources

Exploitability

CWE
CWE Icon
KEV
KEV Icon
CWE ID Description
CWE-UNKNOWN

Attack-Flow Graph

AI Quick Actions

Instant insights powered by AI
Executive Summary

This vulnerability is an incorrect access control issue in the delVlanCfg function of TOTOLINK T6 firmware version 4.1.5cu.748_B20211015. It allows unauthenticated attackers to remove VLAN entries by sending a specially crafted POST request to the vulnerable endpoint /cgi-bin/cstecgi.cgi.

Detection Guidance

Detecting this vulnerability requires checking for unauthorized VLAN modifications. Monitor network traffic for POST requests to /cgi-bin/cstecgi.cgi with parameters targeting delVlanCfg. Inspect logs for unusual VLAN entry deletions or modifications from unauthenticated sources.

Impact Analysis

This vulnerability could allow attackers to disrupt network segmentation by removing VLAN configurations, potentially leading to unauthorized access to restricted network segments or services. It may cause network outages or misconfigurations affecting connected devices.

Compliance Impact

This vulnerability allows unauthenticated attackers to remove VLAN entries via crafted POST requests, which could disrupt network segmentation. This may impact compliance with standards requiring network isolation, such as HIPAA for healthcare networks or GDPR for data protection by design.

Mitigation Strategies

Immediately update the TOTOLINK T6 firmware to the latest version. Restrict access to the /cgi-bin/cstecgi.cgi endpoint via firewall rules. Disable unnecessary services and ensure strong authentication for administrative interfaces.

Chat Assistant

Ask questions about this CVE
Hi! I’m here to help you understand CVE-2026-51731. Ask me anything about the vulnerability, its impact, or mitigation strategies.
0/70

EPSS Chart