CVE-2020-14447

Name: CVE-2020-14447
Creator: NVD / NIST
Published: 2020-06-19T14:15:11.183+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.11%

Last modified Jun 17, 2026

CVE-2020-14447 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. An issue was discovered in Mattermost Server before 5.23.0. Large webhook requests allow attackers to cause a denial of service (infinite loop), aka MMSA-2020-0021.. EPSS estimates a 1.11% chance of exploitation in the next 30 days.

Description

An issue was discovered in Mattermost Server before 5.23.0. Large webhook requests allow attackers to cause a denial of service (infinite loop), aka MMSA-2020-0021.

Metrics

CVSS 3.1

7.5/10

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

EPSS Probability

1.11%

61.9th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-835

Affected Software

Vendor	Product	Versions
Mattermost	Mattermost Server	< 5.23.0

References

https://mattermost.com/security-updates/Vendor Advisory
https://mattermost.com/security-updates/Vendor Advisory

Timeline

Published: Jun 19, 2020
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2020-14447?

An issue was discovered in Mattermost Server before 5.23.0. Large webhook requests allow attackers to cause a denial of service (infinite loop), aka MMSA-2020-0021.

How severe is CVE-2020-14447?

CVE-2020-14447 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.11% probability of exploitation in the next 30 days.

How do I fix CVE-2020-14447?

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-2020-14447?

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

Scan your code now

Source: NVD / NIST