CVE-2020-12456

Name: CVE-2020-12456
Creator: NVD / NIST
Published: 2020-08-26T19:15:14.237+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 8.8/10EPSS 3.06%

Last modified Jun 17, 2026

CVE-2020-12456 is a high-severity vulnerability rated 8.8/10 on the CVSS scale. A remote code execution vulnerability in Mitel MiVoice Connect Client before 214.100.1223.0 could allow an attacker to execute arbitrary code in the chat notification window, due to improper rendering of chat messages. A successful exploit could allow an attacker to steal session cookies, perform directory traversal, and execute arbitrary scripts in the context of the Connect client.. EPSS estimates a 3.06% chance of exploitation in the next 30 days.

Description

A remote code execution vulnerability in Mitel MiVoice Connect Client before 214.100.1223.0 could allow an attacker to execute arbitrary code in the chat notification window, due to improper rendering of chat messages. A successful exploit could allow an attacker to steal session cookies, perform directory traversal, and execute arbitrary scripts in the context of the Connect client.

Metrics

CVSS 3.1

8.8/10

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

3.06%

85.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-22

Affected Software

Vendor	Product	Versions
Mitel	Mivoice Connect Client	< 214.100.1223.0

References

https://www.mitel.com/support/security-advisoriesVendor Advisory
https://www.mitel.com/support/security-advisories/mitel-product-security-advisory-20-0006Vendor Advisory
https://www.mitel.com/support/security-advisoriesVendor Advisory
https://www.mitel.com/support/security-advisories/mitel-product-security-advisory-20-0006Vendor Advisory

Timeline

Published: Aug 26, 2020
Last Modified: Jun 17, 2026
Status: Analyzed

Frequently Asked Questions

What is CVE-2020-12456?

How severe is CVE-2020-12456?

CVE-2020-12456 has a CVSS score of 8.8/10 (HIGH severity). The EPSS model estimates a 3.06% probability of exploitation in the next 30 days.

How do I fix CVE-2020-12456?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2020-12456?

Run a free Strix scan to check your systems for this vulnerability.

Scan your code now

Source: NVD / NIST