How severe is CVE-2024-6428?

CVE-2024-6428 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.

Is CVE-2024-6428 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-6428?

CVE-2024-6428 affects Mattermost. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-6428?

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

Does CVE-2024-6428 have an EU (EUVD) identifier?

Yes. CVE-2024-6428 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-47531.

When was CVE-2024-6428 published?

CVE-2024-6428 was published on 2024-07-03 and last updated on 2026-06-17.

CVE-2024-6428

CVE-2024-6428 is a medium-severity vulnerability in Mattermost with a CVSS 3.x base score of 5.3. 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-284.

Key facts

Severity: Medium (CVSS 3.x base score 5.3)
EPSS exploit prediction: 0% (32nd percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-47531
Weakness: CWE-284
Affected product: Mattermost
Published: 2024-07-03
Last modified: 2026-06-17

Description

Mattermost versions 9.8.0, 9.7.x <= 9.7.4, 9.6.x <= 9.6.2, 9.5.x <= 9.5.5 fail to prevent specifying a RemoteId when creating a new user which allows an attacker to specify both a remoteId and the user ID, resulting in creating a user with a user-defined user ID. This can cause some broken functionality in User Management such administrative actions against the user not working.

Frequently asked questions

What is CVE-2024-6428?: Mattermost versions 9.8.0, 9.7.x <= 9.7.4, 9.6.x <= 9.6.2, 9.5.x <= 9.5.5 fail to prevent specifying a RemoteId when creating a new user which allows an attacker to specify both a remoteId and the user ID, resulting in creating a user with a user-defined user ID. This can cause some broken functionality in User Management such administrative actions against the user not working.
How severe is CVE-2024-6428?: CVE-2024-6428 has a CVSS 3.x base score of 5.3, rated medium severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability low.
Is CVE-2024-6428 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (32nd percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-6428?: CVE-2024-6428 affects Mattermost. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-6428?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-6428 have an EU (EUVD) identifier?: Yes. CVE-2024-6428 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-47531.
When was CVE-2024-6428 published?: CVE-2024-6428 was published on 2024-07-03 and last updated on 2026-06-17.

References

https://mattermost.com/security-updates

Affected products (1)

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

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