WebSocket Vulnerability in Mattermost's Calls Plugin
CVE-2025-12689

6.5MEDIUM

Key Information:

Vendor

Mattermost
Status
Mattermost
Vendor
CVE Published:
17 December 2025

What is CVE-2025-12689?

Mattermost versions 11.0.x (up to 11.0.4), 10.12.x (up to 10.12.2), and 10.11.x (up to 10.11.6) are susceptible to a vulnerability due to improper checking of the WebSocket request field for UTF-8 format. This oversight may allow an attacker to exploit the Calls plugin by sending specially crafted malformed requests, leading to potential service crashes or disruptions.

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Affected Version(s)

Mattermost 11.0.0 <= 11.0.4

Mattermost 10.12.0 <= 10.12.2

Mattermost 10.11.0 <= 10.11.6

References

https://mattermost.com/security-updates

CVSS V3.1

Score:
6.5
Severity:
MEDIUM
Confidentiality:
None
Integrity:
None
Availability:
None
Attack Vector:
Network
Attack Complexity:
Low
Privileges Required:
Low
User Interaction:
None
Scope:
Unchanged

Timeline

  • Vulnerability published

  • Vulnerability Reserved

Credit

National Security Agency
JSON
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