CVE-2025-54458: Unauthorized Subscription Creation to Confluence Space in Mattermost Confluence Plugin

Severity: medium (CVSS 5.0 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.2% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2025-08-11 · updated 2026-06-17
Weakness: CWE-862

Description

Mattermost Confluence Plugin version <1.5.0 fails to check the access of the user to the Confluence space which allows attackers to create a subscription for a Confluence space the user does not have access to via the create subscription endpoint.

Affected products

Mattermost Confluence Plugin: before 1.5.0 — fixed in 1.5.0

How to fix

Upgrade to a fixed version: Mattermost Confluence Plugin 1.5.0. Check the vendor advisory for mitigations.

References

https://mattermost.com/security-updates

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