How severe is CVE-2025-2527?

CVE-2025-2527 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-2025-2527 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-2025-2527?

CVE-2025-2527 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-2527?

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

Does CVE-2025-2527 have an EU (EUVD) identifier?

Yes. CVE-2025-2527 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-15177.

When was CVE-2025-2527 published?

CVE-2025-2527 was published on 2025-05-15 and last updated on 2026-06-17.

CVE-2025-2527

CVE-2025-2527 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-2025-15177
Weakness: CWE-863
Affected product: Mattermost Mattermost Server
Published: 2025-05-15
Last modified: 2026-06-17

Description

Mattermost versions 10.5.x <= 10.5.2, 9.11.x <= 9.11.11 failed to properly verify a user's permissions when accessing groups, which allows an attacker to view group information via an API request.

Frequently asked questions

What is CVE-2025-2527?: Mattermost versions 10.5.x <= 10.5.2, 9.11.x <= 9.11.11 failed to properly verify a user's permissions when accessing groups, which allows an attacker to view group information via an API request.
How severe is CVE-2025-2527?: CVE-2025-2527 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-2025-2527 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-2025-2527?: CVE-2025-2527 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-2527?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-2527 have an EU (EUVD) identifier?: Yes. CVE-2025-2527 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-15177.
When was CVE-2025-2527 published?: CVE-2025-2527 was published on 2025-05-15 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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