CVE intelligence and bounded remediation

CVE-2021-21971 — An out-of-bounds write vulnerability exists in the URL_decode functionality of Sealevel Systems, Inc

Medium CVSS 5.9

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.

Severity
Medium
CVSS
5.9 (3.1)
Published
2022-02-04
CISA KEV
Not currently listed
Ecosystem
operating-system
Weaknesses
CWE-787

Affected products

  • sealevel / seaconnect_370w_firmware / 1.3.34

Matched remediation archetype

Buffer bounds, memory safety, and memory corruption

This catalog composition supplies bounded fallback guidance. Explicitly reviewed curated workflows load with the complete record below.

Check exposure

  • Identify affected native-code versions, build flags, architectures, parsers, codecs, drivers, and input paths in all shipped artifacts.
  • Determine whether untrusted data reaches the affected routine and the process privilege, sandbox, and network exposure.
  • Confirm statically linked, vendored, firmware, and platform-provided copies, not only package-manager records.

Remediate safely

  • Apply the maintained upstream correction or replace the affected component, then rebuild every dependent artifact from clean inputs.
  • Adopt bounds-checked interfaces, validated sizes and integer conversions, clear ownership, and memory-safe components where practical.
  • Enable supported compiler and runtime hardening and add sanitized tests and fuzz regression seeds derived from non-weaponized fixtures.

Authoritative sources

Complete CVE record and remediation plan

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