CVE-2024-1402 - CVE House
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Status published Medium CVE-2024-1402

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

Vulnerability 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. 

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • Gian Klug (coderion)

References

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Affected Vendor

Affected Software

Mattermost
Vulnerable Versions:
0, 9.3.0, 9.2.4, 9.1.5, 8.1.8

Timeline

Official Publish: February 9th, 2024
Last Modified: August 1st, 2024
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:L

Weaknesses (CWE)

CWE-400

MITRE ATT&CK TTPs

T1499 Endpoint Denial of Service
Impact
T1498 Network Denial of Service
Impact