Vulnerability · Published Apr 16, 2025 · Assigned by Mattermost
CVE-2025-27936Webhook Secret Exposure via Timing attack in MSteams plugin
Medium 5.3
In plain English
A medium-severity security flaw in Mattermost from Mattermost. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
Mattermost Plugin MSTeams versions <2.1.0 and Mattermost Server versions 10.5.x <=10.5.1 with the MS Teams plugin enabled fail to perform constant time comparison on a MSTeams plugin webhook secret which allows an attacker to retrieve the webhook secret of the MSTeams plugin via a timing attack during webhook secret comparison.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-plugin-msteams | 2.1.0 | GHSA-2j87-p623-8cc2 |
| Go | github.com/mattermost/mattermost-plugin-msteams | no fix listed | GO-2025-3618 |
| Go | github.com/mattermost/mattermost-server | 10.5.2+incompatible | GO-2025-3618 |
| Go | github.com/mattermost/mattermost-server/v5 | no fix listed | GO-2025-3618 |
| Go | github.com/mattermost/mattermost-server/v6 | no fix listed | GO-2025-3618 |
| Go | github.com/mattermost/mattermost/server/v8 | 8.0.0-20250218121836-2b5275d87136 | GO-2025-3618 |
| Go | github.com/mattermost/mattermost/server/v8 | 8.0.0-20250314142426-c049748b8863 | GHSA-2j87-p623-8cc2 |
| Go | github.com/mattermost/mattermost/server/v8 | 10.5.2 | GHSA-2j87-p623-8cc2 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost | 10.5.0 – through 10.5.1 |
Weakness: CWE-208 · Vector: CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N