UpHeron
All vulnerabilities

Servers and applications

CVE-2026-18256

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

Severity
Medium 4.3
Published
16 Oct 2026
Last changed
29 Oct 2026
Added to UpHeron
1 Nov 2026
Fixed in
11.7.10, 11.8.6, 11.9.2
Sources
NVD

Affected software

SoftwareAffected versions
MattermostServers and applications · cpe:a:mattermost:mattermost_server
  • From 11.7.0 before 11.7.10
  • From 11.8.0 before 11.8.6
  • From 11.9.0 before 11.9.2
  • Version 11.10.0

References

  • NVD https://nvd.nist.gov/vuln/detail/CVE-2026-18256
  • CVE.org https://www.cve.org/CVERecord?id=CVE-2026-18256