{"id":"CVE-2026-18256","url":"https://www.cyber-defence.io/tools/cve/CVE-2026-18256","generatedAt":"2026-10-28T04:34:56.800Z","title":"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…","description":"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","published":"2026-10-16T08:17:13.000Z","lastModified":"2026-10-16T19:23:19.000Z","status":"Awaiting Analysis","sourceIdentifier":"responsibledisclosure@mattermost.com","cvss":{"version":"3.1","score":4.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N"},"cwe":["CWE-863"],"affected":[],"epss":{"score":0.00162,"percentile":0.05301,"date":"2026-10-27","history":[{"date":"2026-10-16","score":0.00162,"percentile":0.04931}]},"kev":{"listed":false},"exploits":{"count":0,"verified":false,"firstPublished":null,"source":"Exploit-DB (https://gitlab.com/exploit-database/exploitdb)","entries":[]},"verdict":{"level":"low","text":"Lower severity and a low EPSS score (0.16%). Track it; it rarely justifies an emergency change on its own."},"changes":[{"kind":"new","label":"New CVE","at":"2026-10-16T08:17:13.000Z","detail":{"score":"4.3","severity":"MEDIUM","publishedAt":"2026-10-16T08:17:12.863Z"},"summary":"New CVE, medium severity (CVSS 4.3)."}],"references":[{"url":"https://mattermost.com/security-updates","source":"responsibledisclosure@mattermost.com"}],"sources":{"nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-18256","epss":"https://www.first.org/epss/","kev":"https://www.cisa.gov/known-exploited-vulnerabilities-catalog","exploitdb":"https://www.exploit-db.com/"},"licence":"CC BY 4.0 — link back to the CVE Explorer if you publish the results; upstream data remains subject to its own terms."}