CVE-2026-28732 json
Slash command trigger-word update allowed command hijacking
published 2026-05-18 5 mo ago modified 2026-10-14 25 d ago also GHSA-wvcv-9xpm-7mqc , GO-2026-5726 , EUVD-2026-30760
- cvss
- 4.3
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.2%
- EPSS 0.2% chance of exploitation in 30 days, percentile 4%
- public exploits
- 0
- none known
Summary
Mattermost versions 11.5.x <= 11.5.1, 10.11.x <= 10.11.13, 11.4.x <= 11.4.3 Fail to enforce slash command trigger-word uniqueness during command updates which allows an authenticated team member with Manage Own Slash Commands permission to hijack and impersonate existing system or custom slash commands via editing their own slash command trigger to an already-registered trigger through the command update API. Mattermost Advisory ID: MMSA-2026-00597
Patch / fix
- go github.com/mattermost/mattermost/server/v8 8.0.0-20260306123948-f5fe8ded6b63, 10.11.14, 11.4.4, 11.5.2
- go github.com/mattermost/mattermost-server 5.3.2-0.20260306123948-f5fe8ded6b63, 10.11.14+incompatible, 11.4.4+incompatible, 11.5.2+incompatible
- Mattermost Mattermost 10.11.14, 11.4.4, 11.5.2, 11.6.0
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
opensuse advisories openSUSE-SU-2026:21483-1
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 5 mo ago
Exploit prediction
0.15% chance of exploitation in the next 30 days, higher than 4% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N |
| GitHub | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:L/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/mattermost/mattermost/server/v8 | >=11.5.0, <11.5.2 >=10.11.0, <10.11.14 >=11.4.0, <11.4.4 <8.0.0-20260306123948-f5fe8ded6b63 |
11.5.2 10.11.14 11.4.4 8.0.0-20260306123948-f5fe8ded6b63 |
| go | github.com/mattermost/mattermost-server | <5.3.2-0.20260306123948-f5fe8ded6b63 >=10.11.0+incompatible, <10.11.14+incompatible >=11.4.0+incompatible, <11.4.4+incompatible >=11.5.0+incompatible, <11.5.2+incompatible |
5.3.2-0.20260306123948-f5fe8ded6b63 10.11.14+incompatible 11.4.4+incompatible 11.5.2+incompatible |
| go | github.com/mattermost/mattermost-server/v5 | all versions |
no fix listed |
| go | github.com/mattermost/mattermost-server/v6 | all versions |
no fix listed |
Affected products
- Mattermost Mattermost
Classification
- Weakness
-
- CWE-863 Incorrect Authorization
References
Sources
- CVE List CVE-2026-28732
- GitHub Advisory GHSA-wvcv-9xpm-7mqc
- NVD CVE-2026-28732
- OSV GO-2026-5726
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