GHSA-xmfh-3ccg-c9fx

Suggest an improvement
Source
https://github.com/advisories/GHSA-xmfh-3ccg-c9fx
Import Source
https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-xmfh-3ccg-c9fx/GHSA-xmfh-3ccg-c9fx.json
JSON Data
https://api.osv.dev/v1/vulns/GHSA-xmfh-3ccg-c9fx
Aliases
Published
2026-06-22T18:34:16Z
Modified
2026-09-22T14:45:10Z
Severity
  • 3.8 (Low) CVSS_V3 - CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:L/A:L CVSS Calculator
Summary
Mattermost has an Incorrect Authorization issue
Details

Mattermost versions 11.7.x <= 11.7.0, 10.11.x <= 10.11.17 fail to validate bot targets when demoting users to guests which allows a lower-privileged administrator to degrade arbitrary bot accounts via the standard demote-user API.. Mattermost Advisory ID: MMSA-2026-00669

Database specific 
{
    "cwe_ids":  [
        "CWE-863"
    ],
    "github_reviewed":  true,
    "github_reviewed_at":  "2026-09-22T14:38:49Z",
    "nvd_published_at":  "2026-06-22T16:16:42Z",
    "severity":  "LOW"
}
References

Affected packages

Go
github.com/mattermost/mattermost-server

Package

Name
github.com/mattermost/mattermost-server
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost-server

Affected ranges

Type
SEMVER
Events
Introduced
11.7.0
Fixed
11.7.1

Affected versions

11.*
11.7.0

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-xmfh-3ccg-c9fx/GHSA-xmfh-3ccg-c9fx.json"
github.com/mattermost/mattermost-server

Package

Name
github.com/mattermost/mattermost-server
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost-server

Affected ranges

Type
SEMVER
Events
Introduced
10.11.0
Fixed
10.11.18

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-xmfh-3ccg-c9fx/GHSA-xmfh-3ccg-c9fx.json"
github.com/mattermost/mattermost/server/v8

Package

Name
github.com/mattermost/mattermost/server/v8
View open source insights on deps.dev
Purl
pkg:golang/github.com/mattermost/mattermost/server/v8

Affected ranges

Type
SEMVER
Events
Introduced
0 Unknown introduced version / All previous versions are affected
Fixed
8.0.0-20260518160100-9bd77d3fc4d2

Database specific

source 
"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-xmfh-3ccg-c9fx/GHSA-xmfh-3ccg-c9fx.json"