What is CVE-2019-9099?

CVE-2019-9099 is a critical-severity vulnerability in Moxa Mb3170, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2020-03-11.

How severe is CVE-2019-9099?

Critical severity. CVSS v3 base score is 9.8 out of 10.

Buffer overflow in Moxa Mb3170

CVE-2019-9099

An issue was discovered on Moxa MGate MB3170 and MB3270 devices before 4.1, MB3280 and MB3480 devices before 3.1, MB3660 devices before 2.3, and MB3180 devices before 2.1. A Buffer overflow in the built-in web server allows remote attackers to initiate DoS, and probably to execute arbitrary code (issue 1 of 2).

Vulnerability class: Buffer Overflow

Published 2020-03-11 · last modified 2026-06-17.

CVSS v3 metric

CVSS v3 base score 9.8 (Critical). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

EPSS exploit prediction

EPSS: 0.040 (90.3th percentile), scored 2026-09-30.

Low probability of exploitation in the next 30 days, but still tracked. 90th percentile — 90.3% of CVEs in the catalogue have a lower EPSS than this one. How to read EPSS.

EPSS over last 30 days · oldest: 0.040 · newest: 0.040 · change: 0.000

Affected products

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

www.us-cert.gov/ics/advisories/icsa-20-056-01 (US Government Resource, Third Party Advisory)
www.moxa.com/en/support/support/security-advisory/mb3710-3180-3270-3280-3480-36… (Vendor Advisory)

Frequently asked questions

What is CVE-2019-9099?: CVE-2019-9099 is a critical-severity vulnerability in Moxa Mb3170, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 9.8/10. Published 2020-03-11.
How severe is CVE-2019-9099?: Critical severity. CVSS v3 base score is 9.8 out of 10.