CVE-2026-3524
High
Description
Mattermost Plugin Legal Hold versions <=1.1.4 fail to halt request processing after a failed authorization check in ServeHTTP which allows an authenticated attacker to access, create, download, and delete legal hold data via crafted API requests to the plugin's endpoints. Mattermost Advisory ID: MMSA-2026-00621
SeverityHigh
CVSS8.8
Exploit probability—
Product
Mattermost Legal Hold
PublishedApr 6, 2026
First seenApr 6, 2026
Weakness typeCWE-862Missing authorization
How to fix
Update
- mattermost legal_hold1.1.5 or later
Vendor advisories
Affected products
| Product | Affected versions | Fixed in |
|---|---|---|
| mattermost legal_hold | v < 1.1.5 | 1.1.5 |
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