CVE-2026-51683Public exploit

LAN service interruption via unauthenticated configuration write

Published Aug 31, 2026 · Updated Sep 1, 2026

Incorrect access control in TOTOLINK T6 4.1.5cu.748_B20211015 allows remote attackers to alter LAN configuration via an HTTP POST request. The cstecgi.cgi handler routes an unauthenticated topicurl=setLanCfg request to setLanCfg, which applies attacker-supplied LAN addressing parameters without an authorization check. Network adjacency is required, and changing the router's LAN addressing can interrupt local connectivity.

CVSS severity4.3
Medium
EPSS probability0.20%
Next 30 days · Sep 16, 2026
Known exploitationUnconfirmed
Based on sourced intelligence
Hinoki checkNot available
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Summary

What happened

Incorrect access control in TOTOLINK T6 4.1.5cu.748_B20211015 allows remote attackers to alter LAN configuration via an HTTP POST request. The cstecgi.cgi handler routes an unauthenticated topicurl=setLanCfg request to setLanCfg, which applies attacker-supplied LAN addressing parameters without an authorization check. Network adjacency is required, and changing the router's LAN addressing can interrupt local connectivity.

The record

CVE
CVE-2026-51683
Published
Aug 31, 2026
Updated
Sep 1, 2026
Vendor
Unknown vendor
Product
Unknown product
Classifications
CWE-284, T1565.001
Attack vector
adjacent
Privileges
unauthenticated

Timeline

How it unfolded

  1. Aug 31, 2026CVE publishedPublication date reported by the CVE source.
  2. Sep 1, 2026Record updatedLatest update available in the CVE record.

Exploitability

Present is not the same as exploitable

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Is a vulnerable build present?

Affected buildAffected product and version details are unavailable.

What conditions does exploitation require?

Attack vectoradjacent
Required privilegesunauthenticated

What is affected?

Affected products and versions are unavailable in this record.

Published CVSS scores

4.3CISA ADPCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N

CVSS describes severity. EPSS estimates exploitation probability.

Attacks

What attackers are doing with it

Daily unique IPs observed by Shadowserver honeypots for known exploited vulnerabilities (KEVs). Missing observations do not establish an absence of attacks.

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No observations available

Sep 10, 2026Sep 16, 2026
Latest reporting daySep 16, 2026
Latest daily unique IPsUnavailable
Prior 30-day averageUnavailable
SourceShadowserver honeypots (KEV)
Vectoradjacent
Privilegesunauthenticated
Known exploitationUnconfirmed
Public exploitPublished

Weakness, pattern, technique

CWE-284Improper Access Control
T1565.001Stored Data Manipulation

Public exploit references

Labels summarize the accepted research assessment. They do not indicate a test against your environment.

Technologies

Your stack

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Your stack

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