CVE-2024-1402

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

Published Feb 9, 2024 CVSS 3.1 · 4.3 Medium EPSS < 1% KEV · Not listed
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

Vendor Solution

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

Tracking

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Advisories

Source ID Title
EUVD EUVD EUVD-2024-0474 Mattermost vulnerable to denial of service via large number of emoji reactions
Github GHSA Github GHSA GHSA-32h7-7j94-8fc2 Mattermost vulnerable to denial of service via large number of emoji reactions
References
History

No history.

Weaknesses

Sources

Status
PUBLISHED
Assigner
Mattermost
Published
Updated
Aug 1, 2024, 6:40 PM
Reserved
Feb 9, 2024, 2:53 PM
Status
Modified
Published
Feb 9, 2024, 4:15 PM
Modified
Jun 17, 2026, 7:04 AM