CVE-2024-1402

Denial of service in mattermost mobile apps and server via emoji reactions

Description

Mattermost fails to check if a custom emoji reaction exists when sending it to a post and to limit the amount of custom emojis allowed to be added in a post, allowing an attacker sending a huge amount of non-existent custom emojis in a post to crash the mobile app of a user seeing the post and to crash the server due to overloading when clients attempt to retrive the aforementioned post. 

Remediation

Solution:

  • Update Mattermost Server to versions 9.3.0, 9.2.4, 9.1.5, 8.1.8 or higher.

Category

4.3
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.34%
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-2024-1402?
CVE-2024-1402 has been scored as a medium severity vulnerability.
How to fix CVE-2024-1402?
To fix CVE-2024-1402: Update Mattermost Server to versions 9.3.0, 9.2.4, 9.1.5, 8.1.8 or higher.
Is CVE-2024-1402 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2024-1402 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-2024-1402?
CVE-2024-1402 affects Mattermost Mattermost.
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