CVE-2025-49810
Thread summarization allows persistent access to channel
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Required
What an attacker can affect
- Confidentiality
- Low
- Integrity
- None
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
Thread summarization allows persistent access to channel
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- Record
CVE-2025-49810- CVSS 3.1
- 3.5 Low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
EUVDEUVD-2025-25424
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- Record
EUVD-2025-25424- CVSS 3.1
- 3.5 Low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-pwvr-grqg-7vp2
Mattermost Lack of Access Control Validation
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- Record
GHSA-pwvr-grqg-7vp2- CVSS 3.1
- 3.5 Low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
NVD
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- Record
CVE-2025-49810- CVSS 3.1
- 3.5 Low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - CVSS 3.1
- 4.3 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSV
Thread summarization allows persistent access to channel
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- Record
CVE-2025-49810- CVSS 3.1
- 3.5 Low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVGHSA-pwvr-grqg-7vp2
Mattermost Lack of Access Control Validation
Mattermost versions 10.5.x <= 10.5.8 fail to validate access controls at time of access which allows user to read a thread via AI posts
- Record
GHSA-pwvr-grqg-7vp2- CVSS 3.1
- 3.5 Low
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:N/A:N - Weakness
- CWE-863
- Updated
- 2026-11-02
OSVGO-2025-3903 No score
Mattermost Lack of Access Control Validation in github.com/mattermost/mattermost-server
Mattermost Lack of Access Control Validation in github.com/mattermost/mattermost-server
- Record
GO-2025-3903- Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
github.com/mattermost/mattermost-serverGo |
10.5.0 to 10.5.8 | 10.5.9 |
github.com/mattermost/mattermost/server/v8Go |
before 8.0.0-20250721095846-c602a4a78e1f | 8.0.0-20250721095846-c602a4a78e1f |
github.com/mattermost/mattermost-serverGo |
10.5.0 up to 10.5.9 | 10.5.9 |
github.com/mattermost/mattermost-serverGo |
10.5.0+incompatible up to 10.5.9+incompatible | 10.5.9+incompatible |
github.com/mattermost/mattermost-server/v5Go |
All versions | None known |
github.com/mattermost/mattermost-server/v6Go |
All versions | None known |
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-2025-49810 is a low vulnerability (CVSS 3.5) in Mattermost, published August 21, 2025. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.20%, the 10th percentile. Fixed in github.com/mattermost/mattermost-server 10.5.9.