VYPR
Medium severity4.3NVD Advisory· Published Aug 17, 2026· Updated Aug 18, 2026

CVE-2026-16047

CVE-2026-16047

Description

Mattermost versions 11.7.x <= 11.7.6, 10.11.x <= 10.11.21, 11.8.x <= 11.8.3 fail to validate that users have read access to a channel before linking a board to it, which allows an authenticated attacker to discover the membership of private channels on the same team via creating, patching, importing, or bulk-creating boards with an arbitrary channelId. Mattermost Advisory ID: MMSA-2026-00674

AI Insight

LLM-synthesized narrative grounded in this CVE's description and references.

Affected products

2
  • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*+ 1 more
    • cpe:2.3:a:mattermost:mattermost_server:*:*:*:*:*:*:*:*range: >=10.11.0,<10.11.22
    • (no CPE)range: <=11.7.6, <=10.11.21, <=11.8.3

Patches

Vulnerability mechanics

References

1

News mentions

1