Cyber Resilience

CVE-2021-21971

MediumPublic PoC

Published: 04 February 2022

Published
04 February 2022
Modified
21 November 2024
KEV Added
Patch
CVSS Score v3.1 5.9 CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS Score 0.0043 62.8th percentile
Risk Priority 12 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2021-21971 is a medium-severity Out-of-bounds Write (CWE-787) vulnerability in Sealevel Seaconnect 370W Firmware. Its CVSS base score is 5.9 (Medium).

Operationally, ranked in the top 37.2% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

EU & UK References

Vulnerability details

An out-of-bounds write vulnerability exists in the URL_decode functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. A specially-crafted MQTT payload can lead to an out-of-bounds write. An attacker can perform a man-in-the-middle attack to trigger this vulnerability.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

sealevel
seaconnect 370w firmware
1.3.34

Mitigating Controls

Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

addresses: CWE-787

Out-of-bounds writes that corrupt control flow or inject shellcode are rendered non-executable by the same memory protections.

References