How severe is CVE-2025-64641?

CVE-2025-64641 has a CVSS 3.x base score of 4.1, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.

Is CVE-2025-64641 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2025-64641?

CVE-2025-64641 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2025-64641?

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

Does CVE-2025-64641 have an EU (EUVD) identifier?

Yes. CVE-2025-64641 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205062.

When was CVE-2025-64641 published?

CVE-2025-64641 was published on 2025-12-24 and last updated on 2026-06-17.

CVE-2025-64641

CVE-2025-64641 is a medium-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 4.1. 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-863.

Key facts

Severity: Medium (CVSS 3.x base score 4.1)
EPSS exploit prediction: 0% (4th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2025-205062
Weakness: CWE-863
Affected product: Mattermost Mattermost Server
Published: 2025-12-24
Last modified: 2026-06-17

Description

Mattermost versions 11.1.x <= 11.1.0, 11.0.x <= 11.0.5, 10.12.x <= 10.12.3, 10.11.x <= 10.11.7 fail to verify that post actions invoking /share-issue-publicly were created by the Jira plugin which allowed a malicious Mattermost user to exfiltrate Jira tickets when victim users interacted with affected posts

Frequently asked questions

What is CVE-2025-64641?: Mattermost versions 11.1.x <= 11.1.0, 11.0.x <= 11.0.5, 10.12.x <= 10.12.3, 10.11.x <= 10.11.7 fail to verify that post actions invoking /share-issue-publicly were created by the Jira plugin which allowed a malicious Mattermost user to exfiltrate Jira tickets when victim users interacted with affected posts
How severe is CVE-2025-64641?: CVE-2025-64641 has a CVSS 3.x base score of 4.1, rated medium severity. It is exploitable over network with low attack complexity, requires low privileges and user interaction. Impact on confidentiality is low, integrity none, and availability none.
Is CVE-2025-64641 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (4th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2025-64641?: CVE-2025-64641 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2025-64641?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2025-64641 have an EU (EUVD) identifier?: Yes. CVE-2025-64641 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2025-205062.
When was CVE-2025-64641 published?: CVE-2025-64641 was published on 2025-12-24 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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