Security readout for executives and security teams
Plain-English summary
Some Moxa MGate protocol gateways use vulnerable firmware that can expose and decrypt login credentials sent to the HTTP web server. If an attacker obtains those credentials, they could gain administrator access to the gateway, creating serious operational and security risk in industrial environments.
Executive priority
Treat this as high-priority OT risk if affected gateways are present. Compromise could give attackers administrative control of protocol gateways, potentially affecting industrial communications and availability.
Technical view
CVE-2021-4161 is a CWE-319 cleartext transmission issue affecting listed Moxa MGate MB3180, MB3280, and MB3480 firmware versions. CISA records CVSS 3.1 score 9.8, network attack vector, no required privileges, no user interaction, and high confidentiality, integrity, and availability impact.
Likely exposure
Exposure is likely in organizations using the affected Moxa MGate gateway series, especially where HTTP management traffic crosses shared, remote, or poorly segmented OT networks. The supplied sources do not identify internet-wide exposure levels.
Exploitation context
The bundle does not show CISA KEV listing or cite active exploitation. The supported risk is credential disclosure through sniffed and decrypted HTTP login details, potentially leading to administrator control of the gateway.
Researcher notes
Evidence is limited to the provided CVE and CISA advisory metadata. Do not assume exploit activity, affected models beyond the listed series, or specific firmware fixes unless confirmed in vendor or advisory text.
Mitigation direction
- Check Moxa and CISA advisory guidance for fixed firmware or vendor-approved mitigations.
- Inventory affected MGate MB3180, MB3280, and MB3480 devices and firmware versions.
- Restrict management access to trusted administrative networks only.
- Avoid untrusted or shared network paths for gateway administration.
- Monitor for unexpected administrator logins or configuration changes.
Validation and detection
- Confirm whether any listed Moxa MGate models are deployed.
- Record exact model and firmware version for each gateway.
- Verify HTTP management exposure and reachable network segments.
- Review authentication logs for unusual administrator access.
- Track remediation status against vendor or CISA guidance.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-319: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCredential and access behavior lookup
The CVE wording references authentication or credential exposure, so valid-account and credential-access review may help. This is a Glexia inferred lookup path, not an official MITRE, ATT&CK, or CVE Program mapping.
Open ATT&CK lookupCVE-2021-4161 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://www.cisa.gov/uscert/ics/advisories/icsa-21-357-01CVE reference · x_refsource_MISC
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Cleartext Transmission of Sensitive Information
Cleartext Transmission of Sensitive Information represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.