CVE-2026-51769
Unauthenticated MQTT message can restart TOTOLINK T6 cloud update check.
Is CVE-2026-51769 being exploited?
Not confirmed. CVE-2026-51769 does not appear in CISA's Known Exploited Vulnerabilities catalog, which records only exploitation that has been observed and reported publicly. That is evidence of absence of a report, not evidence the flaw is unattacked. EPSS currently estimates a 0.44% probability of exploitation in the next 30 days.
How severe is CVE-2026-51769?
CVE-2026-51769 is rated Critical with a CVSS score of 9.8. Severity describes how bad exploitation would be, not how likely it is: pair it with exploitation evidence before deciding what to patch first.
Is there a patch for CVE-2026-51769?
Yes. A fix has been recorded for CVE-2026-51769. The vendor advisory is the authority on the exact fixed version — apply it from there rather than from a summary.
What does CVE-2026-51769 affect?
CVE-2026-51769 affects TOTOLINK T6 firmware 4.1.5cu.748_B20211015, cs_broker component (MQTT). Confirm the exact affected versions against the vendor advisory before deciding you are exposed.
What should I do about CVE-2026-51769?
Install vendor firmware update; block MQTT from WAN and restrict broker access.
Exploitation status reflects CISA's KEV catalog as we last synced it. Check the catalog directly.
Unauthenticated attacker can send crafted MQTT to cs_broker to restart cloud-update-check, enabling disruption, forced updates, or update-chain abuse.
Immediate action required