How severe is CVE-2025-9084?

CVE-2025-9084 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.

Is CVE-2025-9084 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-9084?

CVE-2025-9084 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-9084?

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

Does CVE-2025-9084 have an EU (EUVD) identifier?

Yes. CVE-2025-9084 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-29172.

When was CVE-2025-9084 published?

CVE-2025-9084 was published on 2025-09-15 and last updated on 2026-06-17.

CVE-2025-9084

CVE-2025-9084 is a low-severity vulnerability in Mattermost Mattermost Server 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-601.

Key facts

Severity: Low (CVSS 3.x base score 3.1)
EPSS exploit prediction: 0% (6th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-29172
Weakness: CWE-601
Affected product: Mattermost Mattermost Server
Published: 2025-09-15
Last modified: 2026-06-17

Description

Mattermost versions 10.5.x <= 10.5.9 fail to properly validate redirect URLs which allows attackers to redirect users to malicious sites via crafted OAuth login URLs

Frequently asked questions

What is CVE-2025-9084?: Mattermost versions 10.5.x <= 10.5.9 fail to properly validate redirect URLs which allows attackers to redirect users to malicious sites via crafted OAuth login URLs
How severe is CVE-2025-9084?: CVE-2025-9084 has a CVSS 3.x base score of 3.1, rated low severity. It is exploitable over network with high attack complexity, requires no privileges and user interaction. Impact on confidentiality is none, integrity low, and availability none.
Is CVE-2025-9084 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (6th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-9084?: CVE-2025-9084 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-9084?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-9084 have an EU (EUVD) identifier?: Yes. CVE-2025-9084 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-29172.
When was CVE-2025-9084 published?: CVE-2025-9084 was published on 2025-09-15 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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