What’s Vulnerable › Vulnerabilities

CVE-2021-33823

• Severity: high (CVSS 7.5 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.3% probability of exploitation in the next 30 days
• Public exploit or detection template: yes
• Published: 2021-06-18 · updated 2026-06-17

Description

An issue was discovered on MOXA Mgate MB3180 Version 2.1 Build 18113012. Attacker could send a huge amount of TCP SYN packet to make web service's resource exhausted. Then the web server is denial-of-service.

Affected products

• Moxa Mgate Mb3180 Firmware: 2.1-build_18113012

References

• https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33823.md
• https://www.moxa.com/en/products/industrial-edge-connectivity/protocol-gateways/modbus-tcp-gateways/mgate-mb3180-mb3280-mb3480-series
• https://github.com/Jian-Xian/CVE-POC/blob/master/CVE-2021-33823.md
• https://www.moxa.com/en/products/industrial-edge-connectivity/protocol-gateways/modbus-tcp-gateways/mgate-mb3180-mb3280-mb3480-series

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