CVE-2021-21962

Name: CVE-2021-21962
Creator: NVD / NIST
Published: 2022-02-04T23:15:10.557+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.1/10EPSS 1.88%

Last modified Jun 17, 2026

CVE-2021-21962 is a high-severity vulnerability rated 8.1/10 on the CVSS scale. A heap-based buffer overflow vulnerability exists in the OTA Update u-download functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. EPSS estimates a 1.88% chance of exploitation in the next 30 days.

Description

A heap-based buffer overflow vulnerability exists in the OTA Update u-download functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. A series of specially-crafted MQTT payloads can lead to remote code execution. An attacker must perform a man-in-the-middle attack in order to trigger this vulnerability.

Metrics

CVSS 3.1

8.1/10

CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

1.88%

76.8th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Sealevel	Seaconnect 370w Firmware	1.3.34

References

https://talosintelligence.com/vulnerability_reports/TALOS-2021-1390Exploit, Third Party Advisory
https://talosintelligence.com/vulnerability_reports/TALOS-2021-1390Exploit, Third Party Advisory

Timeline

Published: Feb 4, 2022
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-21962?

How severe is CVE-2021-21962?

CVE-2021-21962 has a CVSS score of 8.1/10 (HIGH severity). The EPSS model estimates a 1.88% probability of exploitation in the next 30 days.

How do I fix CVE-2021-21962?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-21962?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST