CVE-2025-10545 json
Guest user can add unauthorized team users to private channels
published 2025-10-16 12 mo ago modified 2026-10-19 21 d ago also GHSA-424h-xj87-m937 , GO-2025-4030 , EUVD-2025-34728
- cvss
- 3.1
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 0.3%
- EPSS 0.3% chance of exploitation in 30 days, percentile 26%
- public exploits
- 0
- none known
Summary
Mattermost versions 10.5.x <= 10.5.10, 10.11.x <= 10.11.2 fail to properly validate guest user permissions when adding channel members which allows guest users to add any team members to their private channels via the `/api/v4/channels/{channel_id}/members` endpoint
Patch / fix
- go github.com/mattermost/mattermost/server/v8 8.0.0-20250820115038-ff30b84049f0
- go github.com/mattermost/mattermost-server 10.5.11, 10.5.11+incompatible, 10.11.3, 10.11.3+incompatible
- Mattermost Mattermost 10.5.11, 10.11.3, 10.12.0
- govulncheck-vulndb openSUSE Leap 16.0 0.0.20260723T184607-160000.1.1
- govulncheck-vulndb openSUSE Tumbleweed 0.0.20251105T184115-1.1
opensuse advisories openSUSE-SU-2026:21483-1openSUSE-SU-2025:15710-1
- github.com/mattermost/mattermost@fb9c583 commit
- github.com/mattermost/mattermost@ff30b84 commit
- github.com/mattermost/mattermost#31319 pull request
- github.com/mattermost/mattermost#33827 pull request
CISA SSVC
- Exploitation
- none
- Automatable
- no
- Technical impact
- partial
- Assessed
- 12 mo ago
Exploit prediction
0.33% chance of exploitation in the next 30 days, higher than 26% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 3.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N |
| NVD | 3.1 | 4.3 | CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N |
| GitHub | 3.1 | 3.1 | CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N |
Affected packages
| ecosystem | package | affected | fixed in |
|---|---|---|---|
| go | github.com/mattermost/mattermost/server/v8 | <8.0.0-20250820115038-ff30b84049f0 |
8.0.0-20250820115038-ff30b84049f0 |
| go | github.com/mattermost/mattermost-server | >=10.5.0, <10.5.11 >=10.11.0, <10.11.3 >=10.5.0+incompatible, <10.5.11+incompatible >=10.11.0+incompatible, <10.11.3+incompatible |
10.5.11 10.11.3 10.5.11+incompatible 10.11.3+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
-
github.com
/mattermost/mattermost/pull/31319
web
-
github.com
/mattermost/mattermost/pull/33827
web
-
github.com
/mattermost/mattermost/commit/fb9c583f5e466a566a5122154ef337bbf2238902
web
-
github.com
/mattermost/mattermost/commit/ff30b84049f0193f0570d30e46cffc3602298c67
web
-
mattermost.com
/security-updates
web, vendor-advisory
-
nvd.nist.gov
/vuln/detail/CVE-2025-10545
advisory
-
github.com
/mattermost/mattermost
package
-
github.com
/advisories/GHSA-424h-xj87-m937
advisory
Sources
- CVE List CVE-2025-10545
- GitHub Advisory GHSA-424h-xj87-m937
- NVD CVE-2025-10545
- OSV GO-2025-4030
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