How severe is CVE-2025-27538?

CVE-2025-27538 has a CVSS 3.x base score of 2.2, rated low severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2025-27538 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-27538?

CVE-2025-27538 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-27538?

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

Does CVE-2025-27538 have an EU (EUVD) identifier?

Yes. CVE-2025-27538 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11361.

When was CVE-2025-27538 published?

CVE-2025-27538 was published on 2025-04-16 and last updated on 2026-06-17.

CVE-2025-27538

CVE-2025-27538 is a low-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 2.2. 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-306.

Key facts

Severity: Low (CVSS 3.x base score 2.2)
EPSS exploit prediction: 0% (12th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-11361
Weakness: CWE-306
Affected product: Mattermost Mattermost Server
Published: 2025-04-16
Last modified: 2026-06-17

Description

Mattermost versions 10.5.x <= 10.5.1, 9.11.x <= 9.11.9 fail to enforce MFA checks in PUT /api/v4/users/user-id/mfa when the requesting user differs from the target user ID, which allows users with edit_other_users permission to activate or deactivate MFA for other users, even if those users have not set up MFA.

Frequently asked questions

What is CVE-2025-27538?: Mattermost versions 10.5.x <= 10.5.1, 9.11.x <= 9.11.9 fail to enforce MFA checks in PUT /api/v4/users/user-id/mfa when the requesting user differs from the target user ID, which allows users with edit_other_users permission to activate or deactivate MFA for other users, even if those users have not set up MFA.
How severe is CVE-2025-27538?: CVE-2025-27538 has a CVSS 3.x base score of 2.2, rated low severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2025-27538 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (12th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-27538?: CVE-2025-27538 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-27538?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-27538 have an EU (EUVD) identifier?: Yes. CVE-2025-27538 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-11361.
When was CVE-2025-27538 published?: CVE-2025-27538 was published on 2025-04-16 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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