How severe is CVE-2024-39807?

CVE-2024-39807 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2024-39807 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-39807?

CVE-2024-39807 affects Mattermost. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-39807?

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

Does CVE-2024-39807 have an EU (EUVD) identifier?

Yes. CVE-2024-39807 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-38239.

When was CVE-2024-39807 published?

CVE-2024-39807 was published on 2024-07-03 and last updated on 2026-06-17.

CVE-2024-39807

CVE-2024-39807 is a low-severity vulnerability in Mattermost with a CVSS 3.x base score of 3.1. 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-200.

Key facts

Severity: Low (CVSS 3.x base score 3.1)
EPSS exploit prediction: 0% (26th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-38239
Weakness: CWE-200
Affected product: Mattermost
Published: 2024-07-03
Last modified: 2026-06-17

Description

Mattermost versions 9.5.x <= 9.5.5 and 9.8.0 fail to properly sanitize the recipients of a webhook event which allows an attacker monitoring webhook events to retrieve the channel IDs of archived or restored channels.

Frequently asked questions

What is CVE-2024-39807?: Mattermost versions 9.5.x <= 9.5.5 and 9.8.0 fail to properly sanitize the recipients of a webhook event which allows an attacker monitoring webhook events to retrieve the channel IDs of archived or restored channels.
How severe is CVE-2024-39807?: CVE-2024-39807 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires low privileges and no user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2024-39807 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (26th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-39807?: CVE-2024-39807 affects Mattermost. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-39807?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-39807 have an EU (EUVD) identifier?: Yes. CVE-2024-39807 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-38239.
When was CVE-2024-39807 published?: CVE-2024-39807 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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