FlawAtlas
Search the atlas
CVE-2025-14350 Moderate

Mattermost fails to properly validate team membership when processing channel mentions in github.com/mattermost/mattermost-server

Mattermost fails to properly validate team membership when processing channel mentions in github.com/mattermost/mattermost-server. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. (If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.) The additional affected modules and versions are: github.com/mattermost/mattermost-server/v5 before v5.3.2-0.20251209134645-761e56bb11cc.

Exploit probability 0.2%
Published February 23, 2026
Required by Not available
Last source change February 23, 2026

02 / AFFECTED SOFTWARE

Affected packages

Unknown Unknown

34 explicit affected versions

Go github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost/server/v8
Go github.com/mattermost/mattermost-server
Go github.com/mattermost/mattermost-server/v5
Go github.com/mattermost/mattermost-server/v6
Go github.com/mattermost/mattermost/server/v8

03 / CONNECTIONS

Connected vulnerabilities

related OPENSUSE-SU-2026:21483-1

04 / EVIDENCE

Source records

Open Source Vulnerabilities GHSA-57cc-2pf4-mhmx

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate team membership when processing channel mentions which allows authenticated users to determine the existence of teams and their URL names via posting channel shortlinks and observing the channel_mentions property in the API response. Mattermost Advisory ID: MMSA-2025-00563

View original source
Open Source Vulnerabilities GO-2026-4521

Mattermost fails to properly validate team membership when processing channel mentions in github.com/mattermost/mattermost-server. NOTE: The source advisory for this report contains additional versions that could not be automatically mapped to standard Go module versions. (If this is causing false-positive reports from vulnerability scanners, please suggest an edit to the report.) The additional affected modules and versions are: github.com/mattermost/mattermost-server/v5 before v5.3.2-0.20251209134645-761e56bb11cc.

View original source
Open Source Vulnerabilities CVE-2025-14350

Mattermost versions 11.1.x <= 11.1.2, 10.11.x <= 10.11.9, 11.2.x <= 11.2.1 fail to properly validate team membership when processing channel mentions which allows authenticated users to determine the existence of teams and their URL names via posting channel shortlinks and observing the channel_mentions property in the API response. Mattermost Advisory ID: MMSA-2025-00563

View original source

05 / REFERENCES

Further evidence