Improper access control in Sealevel
Priority HIGH 72CWE-284Published · Updated
Key facts
- Attack vector
- Network
- Privileges required
- None
- User interaction
- Required
- Attack complexity
- Low
- Impact type
- Security bypass
- Confidentiality · integrity · availability
- None · None · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · NVD. Fix status from CNA. Impact type from CWE-284.
Summary
A denial of service vulnerability exists in the Modbus configuration functionality of Sealevel Systems, Inc. SeaConnect 370W v1.3.34. Specially-crafted network packets can lead to denial of service. An attacker can send a malicious packet to trigger this vulnerability.
Why it matters now
Exploitation Proof of concept CISA SSVC · not in CISA KEV
EPSS 0.00711 53rd percentileScored 2026-11-07
Public exploit Yes 1 exploit referenceTagged by NVD
Fix No fix listed No fixed version in the sources yet
SSVC decision points
CISA ADP · SSVC 2.0.3
- Exploitation
- Poc
- Automatable
- Yes
- Technical impact
- Partial
The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| — | Sealevel | Sealevel Systems, Inc. SeaConnect 370W v1.3.34 | — | No fix listed | CNA |
- Sealevel Vendor— Affected Sealevel Systems, Inc. SeaConnect 370W v1.3.34 Fixed in — No fix listed CNA
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-21964
- 2026-10-03 Alias added: GHSA-p3rx-9gw8-x632
References
More Sealevel Seaconnect 370w Firmware vulnerabilities
- TI-2021-05006 Stack-based buffer overflow in Sealevel CVSS 3.1CRITICAL 10.0
- TI-2021-05005 Stack-based buffer overflow in Sealevel CVSS 3.1CRITICAL 10.0
- TI-2021-05010 Improper access control in Sealevel CVSS 3.1CRITICAL 9.3
- TI-2021-05013 Improper input validation in Sealevel CVSS 3.1HIGH 8.3
- TI-2021-05007 Heap-based buffer overflow in Sealevel CVSS 3.1HIGH 8.1
- TI-2021-05015 Buffer overflow in Sealevel CVSS 3.1HIGH 8.1
Sources
- CVE-2021-21964 · CVE Program
- CVE-2021-21964 · NVD
- FIRST EPSS
- GHSA-p3rx-9gw8-x632 · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences