# CVE-2026-66404: Ecovacs DEEBOT PRO M1 and K1VAC missing MQTT server certificate verification

Source: https://junglewise.ai/threats/cve-2026-66404-ecovacs-deebot-pro-m1-and-k1vac-missing-mqtt-server-certificate  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-10. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-66404 · Severity: medium · CVSS 6.5 · Published 2026-08-10

Robotic vacuum cleaners DEEBOT PRO M1 and K1VAC fail to validate server certificates in MQTT communications, allowing attackers to intercept and retrieve stored operation logs and activity logs without authentication. An attacker positioned on the same network or performing a man-in-the-middle attack can capture sensitive activity data and robot movement history, compromising user privacy and potentially revealing patterns of home occupancy.

Technologies: [Ecovacs DEEBOT PRO K1VAC](https://junglewise.ai/threats/technologies/deebot-pro-k1vac), [Ecovacs DEEBOT PRO M1](https://junglewise.ai/threats/technologies/deebot-pro-m1). Vendors: [Ecovacs](https://junglewise.ai/threats/vendors/ecovacs).

## Quick answers

**Is CVE-2026-66404 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-66404 being exploited in the wild.

**How severe is CVE-2026-66404?** Medium severity, with a CVSS score of 6.5, published 10 August 2026.

**Which products and versions are affected?** Ecovacs DEEBOT PRO K1VAC prior to V1.7.821; Ecovacs DEEBOT PRO M1 prior to M1-1.7.27.

**Is there a fix for CVE-2026-66404?** A patch was published on 2026-01-31: Initial patches released: M1-1.7.27 and K1VAC-1.7.821 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-66404 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-66404?** Check whether you run Ecovacs DEEBOT PRO K1VAC or Ecovacs DEEBOT PRO M1 at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

The vulnerability is a missing server certificate verification issue (CWE-295) in MQTT communications used by the affected robotic vacuums. The devices do not properly validate TLS certificates when connecting to MQTT brokers, enabling man-in-the-middle (MITM) attacks. An attacker with network access or capable of intercepting traffic can impersonate the legitimate MQTT server and trick the device into sending operation logs and activity logs without authentication. The attack requires network-adjacent position or the ability to intercept/redirect traffic, but no prior authentication or special privileges. Patches addressing this vulnerability were released in January 2026 (firmware versions M1-1.7.27 and K1VAC-1.7.821), with an additional library update for M1 in March 2026.

## Affected products

- Ecovacs DEEBOT PRO M1 prior to M1-1.7.27
- Ecovacs DEEBOT PRO K1VAC prior to V1.7.821

## Timeline

- 2026-07-31: disclosed: Vulnerability disclosed via JVNVU#92804348
- 2026-01-31: patched: Initial patches released: M1-1.7.27 and K1VAC-1.7.821
- 2026-03-23: patched: Additional library update for M1; V1.7.821 update for K1VAC
- 2026-08-10: advisory: CVE-2026-66404 published on NVD

## References

- [https://jvn.jp/en/vu/JVNVU92804348/](https://jvn.jp/en/vu/JVNVU92804348/)
- [https://robot.hellohas.co.jp/news/update_20260331/](https://robot.hellohas.co.jp/news/update_20260331/)

## Related threats

- [Ecovacs DEEBOT PRO authentication bypass in WebSocket](https://junglewise.ai/threats/cve-2026-66411-ecovacs-deebot-pro-authentication-bypass-in-websocket)
- [ECOVACS DEEBOT PRO weak Wi-Fi hotspot password](https://junglewise.ai/threats/cve-2026-66409-ecovacs-deebot-pro-weak-wi-fi-hotspot-password)
- [ECOVACS DEEBOT PRO weak root account password](https://junglewise.ai/threats/cve-2026-66408-ecovacs-deebot-pro-weak-root-account-password)
- [ECOVACS DEEBOT PRO broken cryptographic algorithm in WebSocket authentication](https://junglewise.ai/threats/cve-2026-66407-ecovacs-deebot-pro-broken-cryptographic-algorithm-in-websocket)
- [ECOVACS DEEBOT PRO M1 and K1VAC man-in-the-middle attack via wget without certificate validation](https://junglewise.ai/threats/cve-2026-66406-ecovacs-deebot-pro-m1-and-k1vac-man-in-the-middle-attack-via-wget)