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TI-2023-04061 Aliases CVE-2023-4397GHSA-rx6q-hj2g-x8wp

Buffer overflow in Zyxel ATP series firmware

Priority LOW 20CWE-120Published · Updated

Key facts

Attack vector
Local
Privileges required
High
User interaction
None
Attack complexity
Low
Impact type
Denial of service
Confidentiality · integrity · availability
None · None · High
Fix status
No fix listed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-120 and the CVSS impact.

Summary

A buffer overflow vulnerability in the Zyxel ATP series firmware version 5.37, USG FLEX series firmware version 5.37, USG FLEX 50(W) series firmware version 5.37, and USG20(W)-VPN series firmware version 5.37, could allow an authenticated local attacker with administrator privileges to cause denial-of-service (DoS) conditions by executing the CLI command with crafted strings on an affected device.

Why it matters now

EPSS 0.00233 14th percentileScored 2026-11-07
Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

VendorProductAffected versionsFixed inStatusSource
ZyxelATP series firmware5.37—No fix listedCNA
ZyxelUSG FLEX series firmware5.37—No fix listedCNA
Zyxel USG FLEX 50(W) series firmware5.37—No fix listedCNA
ZyxelUSG20(W)-VPN series firmware5.37—No fix listedCNA
  • ATP series firmware VendorZyxel Affected 5.37 Fixed in — No fix listed CNA
  • USG FLEX series firmware VendorZyxel Affected 5.37 Fixed in — No fix listed CNA
  • USG FLEX 50(W) series firmware VendorZyxel Affected 5.37 Fixed in — No fix listed CNA
  • USG20(W)-VPN series firmware VendorZyxel Affected 5.37 Fixed in — No fix listed CNA

CPE configurations NVD · 16

CPEVersionsRoleVendor
cpe:2.3:o:zyxel:zld:5.37:*:*:*:*:*:*:*5.37VulnerableZyxel
cpe:2.3:h:zyxel:atp100:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:atp100w:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:atp200:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:atp500:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:atp700:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:atp800:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
  • cpe:2.3:o:zyxel:zld:5.37:*:*:*:*:*:*:* Versions 5.37 Vulnerable ·Zyxel
  • cpe:2.3:h:zyxel:atp100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:atp100w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:atp200:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:atp500:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:atp700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:atp800:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_flex_100:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_flex_100w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_flex_200:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Show 6 more CPE
CPEVersionsRoleVendor
cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:usg_20w-vpn:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
cpe:2.3:h:zyxel:vpn50w:-:*:*:*:*:*:*:*not specified by NVDRunning onZyxel
  • cpe:2.3:h:zyxel:usg_flex_50:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_flex_500:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_flex_50w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_flex_700:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:usg_20w-vpn:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
  • cpe:2.3:h:zyxel:vpn50w:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

  • Advisory ·

    Zyxel ATP series firmware, USG FLEX 50(W) series firmware and 2 more products — zyxel.com/global/en/support/security-advisories/zyxel-secur…

    9 records Highest priority Priority MEDIUM 1 MEDIUM, 8 LOW

    Other records, highest priority first

    • TI-2023-04062 Integer overflow in Zyxel ATP series firmwarePriority MEDIUM 41
    • TI-2023-17585 Cross-site scripting in Zyxel ATP series firmwarePriority LOW 28
    • TI-2023-19359 Buffer overflow in Zyxel ATP series firmwarePriority LOW 24
    Show all 9 records → Advisory →

Timeline

  1. 2026-10-02 Threatist record created from CVE-2023-4397
  2. 2026-10-03 Alias added: GHSA-rx6q-hj2g-x8wp

References

Advisory 1

  • TI-2024-10813 Path traversal in Zyxel ATP series firmware KEVCVSS 3.1CRITICAL 9.8
  • TI-2020-15281 A stack-based buffer overflow in fbwifi_continue.cgi on Zyxel UTM and VPN series of… CVSS 3.1CRITICAL 9.8
  • TI-2025-08373 Missing authorization in Zyxel ATP series firmware CVSS 3.1HIGH 8.1
  • TI-2023-04062 Integer overflow in Zyxel ATP series firmware CVSS 3.1HIGH 7.5
  • TI-2024-28064 NULL pointer dereference in Zyxel ATP series firmware CVSS 3.1HIGH 7.5
  • TI-2024-28063 OS command injection in Zyxel ATP series firmware CVSS 3.1HIGH 8.1
See all 20 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences