6.5

CVSS Score

3.1

-

CVSS Score

Basic Information

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CVE-2025-12689

CVE-2025-12689: DoS in Calls plugin via malformed UTF-8 in WebSocket request

Mattermost versions 11.0.x <= 11.0.4, 10.12.x <= 10.12.2, 10.11.x <= 10.11.6 fail to check WebSocket request field for proper UTF-8 format, which allows attacker to crash Calls plug-in via sending malformed request.

(GitHub Advisory)

Miggo Vulnerability Database

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CVE-2025-12689

CVE-2025-12689:

6.5

CVSS Score

3.1

-

CVSS Score

Basic Information

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Technical Details

Package Name	Ecosystem	Vulnerable Versions	First Patched Version
github.com/mattermost/mattermost-plugin-calls	go	< 1.11.0	1.11.0

Technical Details

Vulnerability Intelligence
Miggo AI

Root Cause Analysis

The analysis of the security patch f68b41980e1274e05cf91c687e2af1a73c5e36ca clearly indicates that the vulnerability is located in the WebSocketMessageHasBeenPosted function within the server/websocket.go file. The vulnerability description specifies a failure to check for proper UTF-8 format in a WebSocket request, which could crash the Calls plug-in. The patch directly addresses this by introducing a UTF-8 validation check (utf8.ValidString(req.Action)) at the entry point of this function, before the req.Action string is processed. Prior to the patch, the function would process the req.Action field directly, which, if malformed, could lead to a runtime panic when used in string manipulation functions like strings.TrimPrefix, causing a denial of service. Therefore, Plugin.WebSocketMessageHasBeenPosted is the function that would appear in a runtime profile when the vulnerability is triggered.

Vulnerable functions

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WAF Protection Rules

WAF Rule

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Reasoning

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