Vulnerability · Published Apr 9, 2026 · Assigned by Mattermost
CVE-2026-24661Unbounded Request Body Read in MS Teams Plugin {{/changes}} Webhook Endpoint
Low 3.7
In plain English
A low-severity resource allocation without limits 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 25% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Severity (CVSS 3.1)3.7Low
Exploit odds (30 days)0.3%top 75.3% of all CVEs
Exploited in the wildNo reportsCISA SSVC: none
Attack toolingNoneno public tooling known
Official description
Mattermost Plugins versions <=2.1.3.0 fail to limit the request body size on the {{/changes}} webhook endpoint which allows an authenticated attacker to cause memory exhaustion and denial of service via sending an oversized JSON payload. Mattermost Advisory ID: MMSA-2026-00611
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| Go | github.com/mattermost/mattermost-plugin-msteams | 1.15.1-0.20260213190728-6fe4d295592e | GHSA-5rfv-h47g-xj42 |
| Go | github.com/mattermost/mattermost-plugin-msteams | 1.15.1-0.20260213190728-6fe4d295592e | GO-2026-5153 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Mattermost | Mattermost | 0 – through 2.1.3 |
Weakness: CWE-770 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:N/A:L
References
- MMSA-2026-00611 vendor-advisory