How severe is CVE-2024-39836?

CVE-2024-39836 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2024-39836 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2024-39836?

CVE-2024-39836 affects Mattermost. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2024-39836?

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

Does CVE-2024-39836 have an EU (EUVD) identifier?

Yes. CVE-2024-39836 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-2555.

When was CVE-2024-39836 published?

CVE-2024-39836 was published on 2024-08-22 and last updated on 2026-06-17.

CVE-2024-39836

CVE-2024-39836 is a medium-severity vulnerability in Mattermost with a CVSS 3.x base score of 4.8. 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-693.

Key facts

Severity: Medium (CVSS 3.x base score 4.8)
EPSS exploit prediction: 0% (18th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2024-2555
Weakness: CWE-693
Affected product: Mattermost
Published: 2024-08-22
Last modified: 2026-06-17

Description

Mattermost versions 9.9.x <= 9.9.1, 9.5.x <= 9.5.7, 9.10.x <= 9.10.0 and 9.8.x <= 9.8.2 fail to ensure that remote/synthetic users cannot create sessions or reset passwords, which allows the munged email addresses, created by shared channels, to be used to receive email notifications and to reset passwords, when they are valid, functional emails.

Frequently asked questions

What is CVE-2024-39836?: Mattermost versions 9.9.x <= 9.9.1, 9.5.x <= 9.5.7, 9.10.x <= 9.10.0 and 9.8.x <= 9.8.2 fail to ensure that remote/synthetic users cannot create sessions or reset passwords, which allows the munged email addresses, created by shared channels, to be used to receive email notifications and to reset passwords, when they are valid, functional emails.
How severe is CVE-2024-39836?: CVE-2024-39836 has a CVSS 3.x base score of 4.8, rated medium severity. It is exploitable over network with high attack complexity, requires no privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2024-39836 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (18th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2024-39836?: CVE-2024-39836 affects Mattermost. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2024-39836?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2024-39836 have an EU (EUVD) identifier?: Yes. CVE-2024-39836 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2024-2555.
When was CVE-2024-39836 published?: CVE-2024-39836 was published on 2024-08-22 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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