CVE-2026-51760

Status: DeferredCritical (9.8)—

Incorrect access control in the informSyncUpgfw function of TOTOLINK T6 4.1.5cu.748_B20211015 allows unauthenticated attackers to mass-trigger firmware update activity across mesh slaves via sending a crafted MQTT message to the cs_broker component.

CVSS

Version: 3.1
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Base score: 9.8

Exploitation probability (EPSS)

Probability of exploitation in the next 30 days: 0.64%
Percentile among all scored CVEs: 49
Score date: 10/4/2026

EPSS (Exploit Prediction Scoring System, FIRST) estimates how likely a vulnerability is to be exploited in the wild within 30 days. It complements CVSS (impact) and CISA KEV (confirmed exploitation).

🎯 ATT&CK techniques

How this vulnerability is exploited and what the attacker gains, in MITRE ATT&CK terms.

ExploitationT1190 Exploit Public-Facing Applicationinitial access95 %
Primary impactT1529 System Shutdown/Rebootimpact85 %
Secondary impactT1499.004 Application or System Exploitationimpact75 %

AV:N/PR:N/UI:N indica red sin autenticación (T1190). La vulnerabilidad permite triggering masivo de actualizaciones de firmware en dispositivos mesh, causando disruption (T1529) y potencial DoS de servicios (T1499.004). CWE-284 (access control) facilita acceso no autorizado.

Inferred by our analysis agent from the official description, CVSS vector and CWE, and checked by a supervisor. May contain errors.

🛡️ ATT&CK mitigations that cover these techniques

Filter Network Traffic Vulnerability Scanning Privileged Account Management Network Segmentation Limit Access to Resource Over Network Application Isolation and Sandboxing

Affected technologies (1)

⚠ AI-inferred from the description — NVD hasn't analyzed this CVE yet, these aren't verified CPEs.

Totolink — T6^AI

CWEs

CWE-284

References

Raw JSON (NVD)

Show

{
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          "timestamp": "2026-09-02T17:46:23.234717Z"
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          "integrityImpact": "HIGH",
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  "published": "2026-09-01T14:17:36.407",
  "references": [
    {
      "url": "https://github.com/DarkBoulder/CVE-Vendor-Coordination/blob/main/TOTOLINK/README.md",
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    },
    {
      "url": "https://github.com/ShengWu00/CVE-Vendor-Coordination/blob/main/TOTOLINK/README.md",
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      "url": "https://www.totolink.net/",
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    }
  ],
  "lastModified": "2026-09-03T17:21:57.410",
  "sourceIdentifier": "cve@mitre.org"
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