CVE-2026-5139
published 2026-06-22CVE-2026-5139: Mattermost versions 11.7.x }} slash command.. Mattermost Advisory ID: MMSA-2026-00644
PriorityP430medium5.4CVSS 3.1
AVNACLPRLUINSUCNILAL
EPSS
0.29%
21.1th percentile
Mattermost versions 11.7.x }} slash command.. Mattermost Advisory ID: MMSA-2026-00644
Affected
12 ranges
| Vendor | Product | Version range | Fixed in |
|---|---|---|---|
| github.com | mattermost_mattermost-server | >= 10.11.0 < 10.11.18 | 10.11.18 |
| github.com | mattermost_mattermost-server | >= 11.5.0 < 11.5.6 | 11.5.6 |
| github.com | mattermost_mattermost-server | >= 11.6.0 < 11.6.3 | 11.6.3 |
| github.com | mattermost_mattermost-server | >= 11.7.0 < 11.7.1 | 11.7.1 |
| mattermost | mattermost | 10.11.0 – 10.11.17 | — |
| mattermost | mattermost | 11.5.0 – 11.5.5 | — |
| mattermost | mattermost | 11.6.0 – 11.6.2 | — |
| mattermost | mattermost | 11.7.0 – 11.7.0 | — |
| mattermost | mattermost_server | >= 10.11.0 < 10.11.18 | 10.11.18 |
| mattermost | mattermost_server | >= 11.5.0 < 11.5.6 | 11.5.6 |
| mattermost | mattermost_server | >= 11.6.0 < 11.6.3 | 11.6.3 |
| mattermost | mattermost_server | >= 11.7.0 < 11.7.1 | 11.7.1 |
Stop checking back — get the weekly exploitation signal.
Every Monday: what got weaponized or added to CISA KEV in the last seven days — each CVE cross-linked to its PoC, Nuclei template, and detection rule. Free, one email a week, unsubscribe in one click.
GHSA
Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to enforce administrator authorization on the call within the
ghsa_unreviewed·2026-06-22
CVE-2026-5139 [MEDIUM] CWE-862 Mattermost versions 11.7.x <= 11.7.0, 11.6.x <= 11.6.2, 11.5.x <= 11.5.5, 10.11.x <= 10.11.17 fail to enforce administrator authorization on the call within the
Mattermost versions 11.7.x }} slash command.. Mattermost Advisory ID: MMSA-2026-00644
GHSA
Mattermost doesn't enforce administrator authorization on the call within the command handler
ghsa·2026-06-22
CVE-2026-5139 [MEDIUM] CWE-862 Mattermost doesn't enforce administrator authorization on the call within the command handler
Mattermost doesn't enforce administrator authorization on the {{setDefaultInstance}} call within the {{/gitlab connect}} command handler
Mattermost versions 11.7.x }} slash command.. Mattermost Advisory ID: MMSA-2026-00644
No detection rules found.
No public exploits indexed.
No writeups or analysis indexed.
2026-06-22
Published