CVE-2026-16047
4.3
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N
Summary
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
Affected Software
| Vendor | Product | Version Range | Status |
|---|---|---|---|
| Mattermost | Mattermost | 11.7.0 <= 11.7.6 | affected |
| Mattermost | Mattermost | 10.11.0 <= 10.11.21 | affected |
| Mattermost | Mattermost | 11.8.0 <= 11.8.3 | affected |
| Mattermost | Mattermost | 11.9.0 | unaffected |
| Mattermost | Mattermost | 11.7.7 | unaffected |
| Mattermost | Mattermost | 10.11.22 | unaffected |
| Mattermost | Mattermost | 11.8.4 | unaffected |
Weaknesses
- CWE-862: CWE-862: Missing Authorization
ADP Enrichment
CISA ADP Vulnrichment
- SSVC:
- Exploitation: none
- Automatable: no
- Technical Impact: partial
References
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