Is CVE-2026-3115 actively exploited?

CVE-2026-3115 has no public evidence of in-the-wild exploitation as of 2026-03-30.

What is the CVSS score for CVE-2026-3115?

CVE-2026-3115 has a CVSS score of 4.3 (MEDIUM severity). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N.

How do I patch CVE-2026-3115?

Patch guidance is available from mattermost security advisories. CVEDatabase generates AI-assisted remediation guidance on demand for CVE-2026-3115.

CVE-2026-3115 - remediation guidance & executive summary

Q: Which products are affected by CVE-2026-3115?

4 products: mattermost mattermost server, mattermost mattermost server, mattermost mattermost server, mattermost mattermost server.

Description

Mattermost versions 11.2.x <= 11.2.2, 10.11.x <= 10.11.10, 11.4.x <= 11.4.0, 11.3.x <= 11.3.1 fail to apply view restrictions when retrieving group member IDs, which allows authenticated guest users to enumerate user IDs outside their allowed visibility scope via the group retrieval endpoint.. Mattermost Advisory ID: MMSA-2026-00594

CVSS Metrics

Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Attack Vector: network
Complexity: low
Privileges: low
User Action: none
Scope: unchanged
Confidentiality: low
Integrity: none
Availability: none
Weaknesses: CWE-863 · Incorrect Authorization

Metadata

Primary Vendor: MATTERMOST
Published: 3/26/2026
Last Modified: 3/30/2026
Source: NIST NVD
Note: Verify all details with official vendor sources before applying patches.

Affected Products

mattermost : mattermost_servermattermost : mattermost_servermattermost : mattermost_servermattermost : mattermost_server

Remediation Guidance

Executive Summary

Cite this page

CVE-2026-3115. CVEDatabase.com. Retrieved 1 May 2026. https://cvedatabase.com/cve/CVE-2026-3115

View on NIST NVD

CVE-2026-3115 vulnerability