CVE-2024-1402: Denial of service in mattermost mobile apps and server via emoji reactions

Published Feb 9, 2024
·
Updated

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.

Other sources

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. Fetching posts with huge amounts of reactions results in Uncontrolled Resource Consumption.

GitHub

Affected Software

6 affected componentsFixes available
go/github.com/mattermost/mattermost/server/v8>=9.1.0<9.1.5
9.1.5
go/github.com/mattermost/mattermost/server/v8>=9.2.0<9.2.4
9.2.4
go/github.com/mattermost/mattermost/server/v8<8.1.8
8.1.8
Mattermost Mattermost Server<=8.1.7
Mattermost Mattermost Server>=9.0.0<=9.1.4
Mattermost Mattermost Server>=9.2.0<=9.2.3

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade go/github.com/mattermost/mattermost/server/v8 to a version that resolves this vulnerability.

    Fixed in 9.1.5
  2. Upgrade

    Upgrade go/github.com/mattermost/mattermost/server/v8 to a version that resolves this vulnerability.

    Fixed in 9.2.4
  3. Upgrade

    Upgrade go/github.com/mattermost/mattermost/server/v8 to a version that resolves this vulnerability.

    Fixed in 8.1.8
  4. Upgrade

    Upgrade Mattermost Server to a version that resolves this vulnerability.

    Fixed in 9.3.0
  5. Upgrade

    Upgrade Mattermost Server to a version that resolves this vulnerability.

    Fixed in 9.2.4
  6. Upgrade

    Upgrade Mattermost Server to a version that resolves this vulnerability.

    Fixed in 9.1.5
  7. Upgrade

    Upgrade Mattermost Server to a version that resolves this vulnerability.

    Fixed in 8.1.8

Event History

Feb 9, 2024
CVE Published
via MITRE·03:09 PM
Data Sourced
via MITRE·03:09 PM
RemedyDescriptionSeverityWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software
Advisory Published
via GitHub·06:31 PM

Frequently Asked Questions

1

What is the severity of CVE-2024-1402?

The severity of CVE-2024-1402 is classified as a denial-of-service vulnerability.

2

How do I fix CVE-2024-1402?

To fix CVE-2024-1402, upgrade Mattermost to version 9.1.5, 9.2.4, or 8.1.8 or newer.

3

Who is affected by CVE-2024-1402?

CVE-2024-1402 affects Mattermost Server versions before 9.1.5, 9.2.4, and 8.1.8.

4

What is the impact of CVE-2024-1402?

The impact of CVE-2024-1402 allows attackers to crash the mobile app by sending excessive non-existent custom emojis.

5

When was CVE-2024-1402 disclosed?

CVE-2024-1402 was disclosed in 2024, highlighting a critical issue in the Mattermost application.

Contact

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