CVE-2026-18256 — Private team metadata disclosure via the team search API
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to properly restrict private teams from public team search results, which allow…
Published: 2026-10-16 · CVSS: 4.3 · CVSS 3.1
Mattermost versions 11.10.x <= 11.10.0, 11.7.x <= 11.7.9, 11.9.x <= 11.9.1, 11.8.x <= 11.8.5 fail to properly restrict private teams from public team search results, which allows an authenticated user without permission to list private teams to disclose the ID, name, and display name of private teams via a modified team search request. Mattermost Advisory ID: MMSA-2026-00748
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7