How severe is CVE-2024-1402?

CVE-2024-1402 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2024-1402 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-1402?

CVE-2024-1402 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-1402?

Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.

Does CVE-2024-1402 have an EU (EUVD) identifier?

Yes. CVE-2024-1402 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0474.

When was CVE-2024-1402 published?

CVE-2024-1402 was published on 2024-02-09 and last updated on 2026-06-17.

CVE-2024-1402

CVE-2024-1402 is a medium-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 4.3. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 1% (40th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-0474
Weakness: CWE-400
Affected product: Mattermost Mattermost Server
Published: 2024-02-09
Last modified: 2026-06-17

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.

Frequently asked questions

What is CVE-2024-1402?: 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.
How severe is CVE-2024-1402?: CVE-2024-1402 has a CVSS 3.x base score of 4.3, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2024-1402 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (40th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-1402?: CVE-2024-1402 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-1402?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-1402 have an EU (EUVD) identifier?: Yes. CVE-2024-1402 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-0474.
When was CVE-2024-1402 published?: CVE-2024-1402 was published on 2024-02-09 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (1)

cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*

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