GHSA-3vmp-whvv-5v9v

Source

https://github.com/advisories/GHSA-3vmp-whvv-5v9v

Import Source

https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-3vmp-whvv-5v9v/GHSA-3vmp-whvv-5v9v.json

JSON Data

https://api.osv.dev/v1/vulns/GHSA-3vmp-whvv-5v9v

Aliases

Published

2026-06-12T18:31:59Z

Modified

2026-09-10T03:50:55Z

Severity

5.3 (Medium) CVSS_V3 - CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N CVSS Calculator

Summary

Mattermost doesn't validate that a username returned during bot registration belongs to a bot account

Details

Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15, 10.11.x <= 10.11.16 fail to validate that a username returned during bot registration belongs to a bot account, which allows an unprivileged attacker to intercept private messages sent by plugins via direct message channels by pre-registering a user account with a predictable plugin bot username. Mattermost Advisory ID: MMSA-2026-00649

Database specific

{
    "cwe_ids": [
        "CWE-200"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-08-24T21:39:13Z",
    "nvd_published_at": "2026-06-12T17:16:26Z",
    "severity": "MODERATE"
}

References

Affected packages

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

11.6.0

Fixed

11.6.1

Affected versions

11.*

11.6.0

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-3vmp-whvv-5v9v/GHSA-3vmp-whvv-5v9v.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

11.5.0

Fixed

11.5.5

Database specific

last_known_affected_version_range

"<= 11.5.4"

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-3vmp-whvv-5v9v/GHSA-3vmp-whvv-5v9v.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

10.11.17

Database specific

last_known_affected_version_range

"<= 10.11.15"

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-3vmp-whvv-5v9v/GHSA-3vmp-whvv-5v9v.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

8.0.0-20250731163400-5b955468ea1e

Fixed

8.0.0-20260428151657-c79c3831061a

Database specific

source

"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2026/06/GHSA-3vmp-whvv-5v9v/GHSA-3vmp-whvv-5v9v.json"