CVE-2018-21258

Name: CVE-2018-21258
Creator: NVD / NIST
Published: 2020-06-19T17:15:12.787+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.5/10EPSS 1.16%

Last modified Jun 17, 2026

CVE-2018-21258 is a high-severity vulnerability rated 7.5/10 on the CVSS scale. An issue was discovered in Mattermost Server before 5.1. It allows attackers to cause a denial of service via the invite_people slash command.. EPSS estimates a 1.16% chance of exploitation in the next 30 days.

Description

An issue was discovered in Mattermost Server before 5.1. It allows attackers to cause a denial of service via the invite_people slash command.

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

1.16%

63.0th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-74

Affected Software

Vendor	Product	Versions
Mattermost	Mattermost Server	< 5.1.0

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-2018-21258?

An issue was discovered in Mattermost Server before 5.1. It allows attackers to cause a denial of service via the invite_people slash command.

How severe is CVE-2018-21258?

CVE-2018-21258 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 1.16% probability of exploitation in the next 30 days.

How do I fix CVE-2018-21258?

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-2018-21258?

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

Scan your code now

Source: NVD / NIST