How severe is CVE-2026-2462?

CVE-2026-2462 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.

Is CVE-2026-2462 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-2462?

CVE-2026-2462 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-2462?

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

Does CVE-2026-2462 have an EU (EUVD) identifier?

Yes. CVE-2026-2462 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12413.

When was CVE-2026-2462 published?

CVE-2026-2462 was published on 2026-03-16 and last updated on 2026-06-17.

CVE-2026-2462

CVE-2026-2462 is a medium-severity vulnerability in Mattermost Mattermost Server with a CVSS 3.x base score of 6.6. 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 6.6)
EPSS exploit prediction: 0% (25th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-12413
Weakness: CWE-863
Affected product: Mattermost Mattermost Server
Published: 2026-03-16
Last modified: 2026-06-17

Description

Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528

Frequently asked questions

What is CVE-2026-2462?: Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to restrict plugin installation on CI test instances with default admin credentials which allows an unauthenticated attacker to achieve remote code execution and exfiltrate sensitive configuration data including AWS and SMTP credentials via uploading a malicious plugin after changing the import directory. Mattermost Advisory ID: MMSA-2025-00528
How severe is CVE-2026-2462?: CVE-2026-2462 has a CVSS 3.x base score of 6.6, rated medium severity. It is exploitable over network with low attack complexity, requires high privileges and no user interaction. Impact on confidentiality is low, integrity low, and availability low.
Is CVE-2026-2462 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (25th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-2462?: CVE-2026-2462 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-2462?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-2462 have an EU (EUVD) identifier?: Yes. CVE-2026-2462 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12413.
When was CVE-2026-2462 published?: CVE-2026-2462 was published on 2026-03-16 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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