CVE-2026-21386
CVE.org · Published
- Record status
- Published
- Identifier year (not publication year)
- 2026
- Source publication
- Source updated
- Imported by cveboard
- Source snapshot
- cve_2026-10-24_midnight_baseline ·
CNA source text (English)
Private channel enumeration via /mute slash command
Mattermost versions 11.3.x <= 11.3.0, 11.2.x <= 11.2.2, 10.11.x <= 10.11.10 fail to use consistent error responses when handling the /mute command which allows an authenticated team member to enumerate private channels they are not authorized to know about via differing error messages for nonexistent versus private channels. Mattermost Advisory ID: MMSA-2026-00588
Scoped product and version facts
Fix information unknown; no fixed version is derived here. Missing information does not prove that no fix exists.
Exploitation unknown; this catalogue does not assess exploitation.
Mattermost
- Vendor
- Mattermost
- Product
- Mattermost
- Platforms
- Unknown
- Default status
unaffected
| Version (version) | Status (status) | Version scheme (versionType) | Exclusive end (lessThan) | Inclusive end (lessThanOrEqual) | Status changes (at → status) |
|---|---|---|---|---|---|
| 11.3.0 | affected | semver | Unavailable | 11.3.0 | None listed |
| 11.2.0 | affected | semver | Unavailable | 11.2.2 | None listed |
| 10.11.0 | affected | semver | Unavailable | 10.11.10 | None listed |
| 11.4.0 | unaffected | Unavailable | Unavailable | Unavailable | None listed |
| 11.3.1 | unaffected | Unavailable | Unavailable | Unavailable | None listed |
| 11.2.3 | unaffected | Unavailable | Unavailable | Unavailable | None listed |
| 10.11.11 | unaffected | Unavailable | Unavailable | Unavailable | None listed |