# CVE-2026-123998: Hisense VIDAA Smart TV MQTT Broker Authentication Bypass

Status: published. Published: 2026-11-06. Updated: 2026-11-06.

Hisense VIDAA Smart TV firmware V0000.01.00a.P0220 contains an authentication bypass vulnerability in its remote-control MQTT broker on TCP port 36669, which accepts publicly documented default credentials and an ineffective 4-digit pairing PIN with no rate limiting or lockout, allowing a brute force of the entire code space in about five seconds, while some actions require no pairing at all. A LAN-adjacent attacker can exploit this to inject key events, change volume, switch input sources, enumerate inputs, launch arbitrary installed applications, and monitor pairing activity, posing a significant risk in hotel deployments where untrusted LAN access is common.

## Remediation

No remediation reported in collected sources

## Affected products and versions

- Hisense / VIDAA: 0000.01.00a.P0220 (affected, custom). Source: CNA: VulnCheck

## Severity and prioritization

- CVSS 4.0: 7.2 (high); CVSS:4.0/AV:A/AC:L/AT:N/PR:N/UI:N/VC:L/VI:H/VA:H/SC:N/SI:N/SA:N; source: CNA: VulnCheck

- CVSS 3.1: 8.3 (high); CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:L/I:H/A:H; source: CNA: VulnCheck

- CISA KEV: No listing in collected sources

- EPSS: Not available

- SSVC: Not available

- Weaknesses: CWE-1392, CWE-307

## Exploit evidence

- exploit: https://github.com/yehia-mamdouh/Hisense-Smart-TV-Security-Research (CNA: VulnCheck)

## References

- https://github.com/yehia-mamdouh/Hisense-Smart-TV-Security-Research (CNA: VulnCheck; technical-description, exploit)

- https://www.vulncheck.com/advisories/hisense-vidaa-smart-tv-mqtt-broker-authentication-bypass (CNA: VulnCheck; third-party-advisory)

## Provenance

- CNA: VulnCheck: https://www.cve.org/CVERecord?id=CVE-2026-123998; retrieved 2026-11-06; source updated 2026-11-06

Revision: 45c253a2ebfbd2348c664e8b1f179775a1a0251cfe129da8c09f0ca6da97e0e4

Canonical: https://y2.dev/cve/CVE-2026-123998

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