CVE-2023-40703

Denial of Service via specially crafted block fields in Mattermost Boards

Description

Mattermost fails to properly limit the characters allowed in different fields of a block in Mattermost Boards allowing a attacker to consume excessive resources, possibly leading to Denial of Service, by patching the field of a block using a specially crafted string. 

Remediation

Solution:

  • Update Mattermost Server to versions 9.1.1, 9.0.2, 7.8.13, 8.1.4 or higher.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.09%
Vendor Advisory mattermost.com
Affected: Mattermost Mattermost
Published at:
Updated at:

References

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

Frequently Asked Questions

What is the severity of CVE-2023-40703?
CVE-2023-40703 has been scored as a medium severity vulnerability.
How to fix CVE-2023-40703?
To fix CVE-2023-40703: Update Mattermost Server to versions 9.1.1, 9.0.2, 7.8.13, 8.1.4 or higher.
Is CVE-2023-40703 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-40703 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.
What software or system is affected by CVE-2023-40703?
CVE-2023-40703 affects Mattermost Mattermost.
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