How severe is CVE-2025-27715?

CVE-2025-27715 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.

Is CVE-2025-27715 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-27715?

CVE-2025-27715 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-27715?

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

Does CVE-2025-27715 have an EU (EUVD) identifier?

Yes. CVE-2025-27715 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7203.

When was CVE-2025-27715 published?

CVE-2025-27715 was published on 2025-03-21 and last updated on 2026-06-17.

CVE-2025-27715

CVE-2025-27715 is a low-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 3.3. 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: Low (CVSS 3.x base score 3.3)
EPSS exploit prediction: 0% (10th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-7203
Weakness: CWE-863
Affected product: Mattermost Mattermost Server
Published: 2025-03-21
Last modified: 2026-06-17

Description

Mattermost versions 9.11.x <= 9.11.8 fail to prompt for explicit approval before adding a team admin to a private channel, which team admins to joining private channels via crafted permalink links without explicit consent from them.

Frequently asked questions

What is CVE-2025-27715?: Mattermost versions 9.11.x <= 9.11.8 fail to prompt for explicit approval before adding a team admin to a private channel, which team admins to joining private channels via crafted permalink links without explicit consent from them.
How severe is CVE-2025-27715?: CVE-2025-27715 has a CVSS 3.x base score of 3.3, rated low severity. It is exploitable over network with high attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability none.
Is CVE-2025-27715 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (10th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-27715?: CVE-2025-27715 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-27715?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-27715 have an EU (EUVD) identifier?: Yes. CVE-2025-27715 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-7203.
When was CVE-2025-27715 published?: CVE-2025-27715 was published on 2025-03-21 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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