How severe is CVE-2024-9155?

CVE-2024-9155 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 low, integrity none, and availability none.

Is CVE-2024-9155 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-9155?

CVE-2024-9155 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-9155?

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

Does CVE-2024-9155 have an EU (EUVD) identifier?

Yes. CVE-2024-9155 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-49759.

When was CVE-2024-9155 published?

CVE-2024-9155 was published on 2024-09-26 and last updated on 2026-06-17.

CVE-2024-9155

CVE-2024-9155 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-863.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (17th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-49759
Weakness: CWE-863
Affected product: Mattermost Mattermost Server
Published: 2024-09-26
Last modified: 2026-06-17

Description

Mattermost versions 9.10.x <= 9.10.1, 9.9.x <= 9.9.2, 9.5.x <= 9.5.8 fail to limit access to channels files that have not been linked to a post which allows an attacker to view them in channels that they are a member of.

Frequently asked questions

What is CVE-2024-9155?: Mattermost versions 9.10.x <= 9.10.1, 9.9.x <= 9.9.2, 9.5.x <= 9.5.8 fail to limit access to channels files that have not been linked to a post which allows an attacker to view them in channels that they are a member of.
How severe is CVE-2024-9155?: CVE-2024-9155 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 low, integrity none, and availability none.
Is CVE-2024-9155 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (17th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-9155?: CVE-2024-9155 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-9155?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-9155 have an EU (EUVD) identifier?: Yes. CVE-2024-9155 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-49759.
When was CVE-2024-9155 published?: CVE-2024-9155 was published on 2024-09-26 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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