CVE-2018-21256

Description

An issue was discovered in Mattermost Server before 5.1. It allows attackers to bypass intended access restrictions (for group-message channel creation) via the Group message slash command.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
CVSS 2.0 •
EPSS 0.15%
Vendor Advisory mattermost.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://mattermost.com/security-updates/ vendor advisory

Frequently Asked Questions

What is the severity of CVE-2018-21256?
CVE-2018-21256 has been scored as a medium severity vulnerability.
How to fix CVE-2018-21256?
To fix CVE-2018-21256, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2018-21256 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2018-21256 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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