CVE-2025-54458: 
vulnerability analysis and mitigation

Mattermost Confluence Plugin version <1.5.0 contains an authorization bypass vulnerability identified as CVE-2025-54458. The vulnerability was discovered and disclosed on August 11, 2025, affecting the plugin's access control mechanism for Confluence spaces (NVD).

The vulnerability stems from a failure to properly check user access permissions to Confluence spaces. This allows attackers with valid authentication to create subscriptions for Confluence spaces they do not have legitimate access to by exploiting the create subscription endpoint. The vulnerability has been assigned a CVSS v3.1 base score of 5.0 (Medium) with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:N/A:N, indicating network accessibility, low attack complexity, and required low privileges (NVD).

The primary impact of this vulnerability is unauthorized access to Confluence spaces through subscription creation. While the attacker needs to be authenticated, they can bypass intended access controls to gain visibility into spaces they should not have access to, potentially leading to information disclosure (NVD).

Users should upgrade their Mattermost Confluence Plugin to version 1.5.0 or later to address this vulnerability. The fix implements proper access control checks for Confluence space subscriptions (NVD).