Description
Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to sanitize sensitive data in WebSocket messages which allows authenticated users to exfiltrate password hashes and MFA secrets via profile nickname updates or email verification events. Mattermost Advisory ID: MMSA-2025-00560
Basic information
- Type
- reviewed
- Severity
- medium
- Advisory on GitHub
- Open advisory ↗
- Repository advisory
- —
- Source code
- Browse source ↗
- Published (advisory)
- 2026-02-16 12:30:25 UTC
- Updated
- 2026-02-19 19:35:13 UTC
- GitHub reviewed
- 2026-02-19 19:35:11 UTC
- NVD published
- 2026-02-16
EPSS Score
| Score |
Percentile |
|
0.04%
|
11.48% |
CVSS Scores
| Base score |
Version |
Severity |
Vector |
|
5.7
|
3.1 |
—
|
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:N/A:N
Click to expand
- Attack vector (AV:N)
- Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
- Attack complexity (AC:L)
- Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
- Privileges required (PR:L)
- A normal user session is enough; they don’t have to be admin.
- User interaction (UI:R)
- A real person has to do something—click, install, enable—otherwise it doesn’t land.
- Scope (S:U)
- Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
- Confidentiality (C:H)
- Serious risk that confidential data gets exposed in a big way.
- Integrity (I:N)
- Data isn’t meaningfully altered or forged.
- Availability (A:N)
- Service keeps running; no real outage angle.
|
CWEs
| CWE id |
Name |
|
CWE-200
|
Exposure of Sensitive Information to an Unauthorized Actor |
Affected packages (5)
Vulnerable version ranges and first patched releases as published by GitHub.
| Ecosystem |
Package |
Vulnerable range |
First patched |
Vulnerable functions |
| go |
github.com/mattermost/mattermost/server/v8 |
< 8.0.0-20251210191531-cd17b61de41b |
8.0.0-20251210191531-cd17b61de41b |
—
|
| go |
github.com/mattermost/mattermost-server |
>= 11.1.0, < 11.1.3 |
— |
—
|
| go |
github.com/mattermost/mattermost-server |
>= 10.11.0, < 10.11.10 |
— |
—
|
| go |
github.com/mattermost/mattermost-server |
>= 11.2.0, < 11.2.2 |
— |
—
|
| go |
github.com/mattermost/mattermost-server |
< 5.3.2-0.20251210191531-cd17b61de41b |
5.3.2-0.20251210191531-cd17b61de41b |
—
|
cvelogic
Threat Intelligence