CRITICAL

CVE-2021-21961

CVSS v3

CRITICAL

EPSS Score

2.6 %

exploit probability, as of 2026-10-19

CISA KEV

known exploited

Exploitation

—

SSVC status

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Affected and fixed versions

Neither OSV.dev nor the vendor advisories we read list affected versions for CVE-2021-21961 yet.

Full record on NVD

Description

A stack-based buffer overflow vulnerability exists in the NBNS functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. A specially-crafted network packet can lead to remote code execution. An attacker can send a malicious packet to trigger this vulnerability.

Technical details

Published: 2022-02-04

Frequently asked questions

What is CVE-2021-21961?

Is CVE-2021-21961 actively exploited?

Active exploitation of CVE-2021-21961 has not been confirmed. Its EPSS score was 2.6% on 2026-10-19, the estimated probability of exploitation in the next 30 days.

What is the CVSS score for CVE-2021-21961?

CVE-2021-21961 has a CVSS v3 base score of 10 (CRITICAL severity).

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