CVE-2021-21961
A stack-based buffer overflow vulnerability exists in the NBNS functionality of Sealevel Systems,...
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.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- None
- User interaction
- None
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
10.0
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.
- Record
CVE-2021-21961- CVSS 3.0
- 10.0 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Weakness
- CWE-121
- Updated
- 2026-11-02
EUVDEUVD-2021-9132
10.0
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.
- Record
EUVD-2021-9132- CVSS 3.0
- 10.0 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-prrr-88p3-mjgq
9.8
A stack-based buffer overflow vulnerability exists in the NBNS functionality of Sealevel Systems,...
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.
- Record
GHSA-prrr-88p3-mjgq- CVSS 3.1
- 9.8 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H - Weakness
- CWE-787
- Updated
- 2026-11-02
NVD
10.0
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.
- Record
CVE-2021-21961- CVSS 3.1
- 10.0 Critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - CVSS 3.0
- 10.0 Critical
CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H - CVSS 2.0
- 7.5 High
AV:N/AC:L/Au:N/C:P/I:P/A:P - Weakness
- CWE-121, CWE-787
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2021-21961 is a critical vulnerability (CVSS 10.0) in Sealevel Seaconnect 370w Firmware, published February 4, 2022. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.64%, the 85th percentile. No source names a fixed version.