CVE-2023-40703: Denial of Service via specially crafted block fields in Mattermost Boards

Published Nov 27, 2023
·
Updated

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.

Affected Software

8 affected componentsFixes available
go/github.com/mattermost/mattermost-server/v6<7.8.13
7.8.13
go/github.com/mattermost/mattermost/server/v8<8.1.4
8.1.4
go/github.com/mattermost/mattermost/server/v8>=9.0.0<9.0.2
9.0.2
go/github.com/mattermost/mattermost/server/v8>=9.1.0<9.1.1
9.1.1
Mattermost Mattermost<=7.8.12
Mattermost Mattermost>=8.0.0<=8.1.3
Mattermost Mattermost>=9.0.0<=9.0.1
Mattermost Mattermost=9.1.0

Remediation

Information

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

Event History

Nov 27, 2023
CVE Published
via MITRE·09:08 AM
Data Sourced
via MITRE·09:08 AM
RemedyDescriptionSeverityWeakness
Advisory Published
12:30 PM

Frequently Asked Questions

1

What is CVE-2023-40703?

CVE-2023-40703 is a vulnerability in Mattermost Boards that allows an attacker to consume excessive resources, possibly leading to a Denial of Service, by patching the field of a block using a specially crafted string.

2

How does CVE-2023-40703 affect Mattermost?

CVE-2023-40703 affects Mattermost versions 7.8.13 up to 9.1.1.

3

What is the severity of CVE-2023-40703?

CVE-2023-40703 has a severity rating of 4.3, which is considered medium.

4

How can I fix CVE-2023-40703?

To fix CVE-2023-40703, it is recommended to update to Mattermost versions 7.8.14, 8.1.5, 9.0.3, or 9.1.2.

5

Where can I find more information about CVE-2023-40703?

You can find more information about CVE-2023-40703 on the Mattermost website, NIST vulnerability database, and GitHub advisory.

Contact

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