CVE-2026-16048
Channel member roles accept out-of-scope roles
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- Low
Exploit likelihood
What each source reports
CVE List Score used
Channel member roles accept out-of-scope roles
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
- Record
CVE-2026-16048- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2026-60206
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
- Record
EUVD-2026-60206- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-v37p-g38w-w7wg
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict...
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
- Record
GHSA-v37p-g38w-w7wg- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-863
- Updated
- 2026-11-02
NVD
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
- Record
CVE-2026-16048- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-863
- Updated
- 2026-11-02
OSV
Channel member roles accept out-of-scope roles
Mattermost versions 11.8.x <= 11.8.2, 11.7.x <= 11.7.6, 10.11.x <= 10.11.21 fail to restrict channel member role assignment to channel-scoped roles which allows a channel administrator to gain additional channel permissions via the channel member roles API.. Mattermost Advisory ID: MMSA-2026-00697
- Record
CVE-2026-16048- CVSS 3.1
- 6.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L - Weakness
- CWE-863
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-16048 is a medium vulnerability (CVSS 6.3) in Mattermost, published August 17, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.26%, the 17th percentile. No source names a fixed version.