How severe is CVE-2026-2463?

CVE-2026-2463 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-2026-2463 being actively exploited?

It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.

What products are affected by CVE-2026-2463?

CVE-2026-2463 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.

How do I fix CVE-2026-2463?

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

Does CVE-2026-2463 have an EU (EUVD) identifier?

Yes. CVE-2026-2463 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12385.

When was CVE-2026-2463 published?

CVE-2026-2463 was published on 2026-03-16 and last updated on 2026-06-17.

CVE-2026-2463

CVE-2026-2463 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-862.

Key facts

Severity: Medium (CVSS 3.x base score 4.3)
EPSS exploit prediction: 0% (7th percentile)
Actively exploited: Not listed in CISA KEV
EU (EUVD) id: EUVD-2026-12385
Weakness: CWE-862
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 filter invite IDs based on user permissions, which allows regular users to bypass access control restrictions and register unauthorized accounts via leaked invite IDs during team creation.. Mattermost Advisory ID: MMSA-2025-00565

Frequently asked questions

What is CVE-2026-2463?: Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to filter invite IDs based on user permissions, which allows regular users to bypass access control restrictions and register unauthorized accounts via leaked invite IDs during team creation.. Mattermost Advisory ID: MMSA-2025-00565
How severe is CVE-2026-2463?: CVE-2026-2463 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-2026-2463 being actively exploited?: It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 0% (7th percentile), an estimate of the probability of exploitation in the next 30 days.
What products are affected by CVE-2026-2463?: CVE-2026-2463 affects Mattermost Mattermost Server. See the affected-products list for the exact vulnerable versions.
How do I fix CVE-2026-2463?: Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround.
Does CVE-2026-2463 have an EU (EUVD) identifier?: Yes. CVE-2026-2463 is tracked in the ENISA EU Vulnerability Database (EUVD) as EUVD-2026-12385.
When was CVE-2026-2463 published?: CVE-2026-2463 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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