CVE-2025-27933: Github.com/mattermost/mattermost/server/v8 Mattermost Allows Members With Permission Vulnerability
MODERATECVE-2025-27933 is a MODERATE (CVSS 5.4) mattermost allows members with permission vulnerability (CWE-863: Incorrect Authorization) affecting Github.com/mattermost/mattermost/server/v8 libraries in the Go ecosystem. The issue involves mattermost allows members with permission to convert public channels to private and convert private to public. Remediation is available by upgrading affected packages to version 10.4.3, 10.3.4, 9.11.9, 8.0.0-20250218135018-e644e3c8e393.
CVE-2025-27933 at a Glance
Security Impact
CVSS: 5.4
The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N).
How to Fix CVE-2025-27933
To remediate this vulnerability, upgrade all affected Github.com/mattermost/mattermost/server/v8 dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.
Upgrade github.com/mattermost/mattermost/server/v8 to 10.4.3Upgrade github.com/mattermost/mattermost/server/v8 to 10.3.4Upgrade github.com/mattermost/mattermost/server/v8 to 9.11.9Upgrade github.com/mattermost/mattermost-server to 9.11.9Upgrade github.com/mattermost/mattermost/server/v8 to 8.0.0-20250218135018-e644e3c8e393Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/mattermost/mattermost/server/v8How to Check if You Are Affected
To determine whether your application is affected by CVE-2025-27933, inspect your project dependencies for Github.com/mattermost/mattermost/server/v8:
inspect dependencies for github.com/mattermost/mattermost/server/v8Analyze the terminal output to locate any version of Github.com/mattermost/mattermost/server/v8 in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 10.4.3), your application is affected.
Note: Verify declared build manifests and deployed runtime container environments.
Technical Details
Vulnerability Mechanism & Technical Analysis
This vulnerability is classified under CWE-863: Incorrect Authorization, where the product performs an authorization check when an actor attempts to access a resource or perform an action, but it does not correctly perform the check. In Github.com/mattermost/mattermost/server/v8, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.
Source Advisory Statement
CVE-2025-27933 Affected Github.com/mattermost/mattermost/server/v8 Versions
5 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/mattermost/mattermost/server/v8
|
Go |
≥ 10.4.0
< 10.4.3
|
10.4.3
|
|
github.com/mattermost/mattermost/server/v8
|
Go |
≥ 10.3.0
< 10.3.4
|
10.3.4
|
|
github.com/mattermost/mattermost/server/v8
|
Go |
≥ 9.11.0
< 9.11.9
|
9.11.9
|
|
github.com/mattermost/mattermost-server
|
Go |
< 9.11.9
|
9.11.9
|
|
github.com/mattermost/mattermost/server/v8
|
Go |
< 8.0.0-20250218135018-e644e3c8e393
|
8.0.0-20250218135018-e644e3c8e393
|
References
Frequently Asked Questions
What is CVE-2025-27933?
Which Github.com/mattermost/mattermost/server/v8 versions are affected?
What version fixes CVE-2025-27933?
Is github.com/mattermost/mattermost/server/v8 affected?
Is github.com/mattermost/mattermost-server affected?
What is the CVSS score of CVE-2025-27933?
What CWE is associated with CVE-2025-27933?
How can I check Go dependencies for CVE-2025-27933?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-h5v9-xw2g-7hrq",
"modified" : "2025-03-21T22:37:04Z",
"published" : "2025-03-21T09:30:35Z",
"aliases" : [ "CVE-2025-27933" ],
"summary" : "Mattermost allows members with permission to convert public channels to private and convert private to public",
"details" : "Mattermost versions 10.4.x <= 10.4.2, 10.3.x <= 10.3.3, 9.11.x <= 9.11.8 fail to to enforce channel conversion restrictions, which allows members with permission to convert public channels to private ones to also convert private ones to public.",
"severity" : [ {
"type" : "CVSS_V3",
"score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost/server/v8"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "10.4.0"
}, {
"fixed" : "10.4.3"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost/server/v8"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "10.3.0"
}, {
"fixed" : "10.3.4"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost/server/v8"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "9.11.0"
}, {
"fixed" : "9.11.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "9.11.9"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost/server/v8"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "8.0.0-20250218135018-e644e3c8e393"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-27933"
}, {
"type" : "PACKAGE",
"url" : "https://github.com/mattermost/mattermost"
}, {
"type" : "WEB",
"url" : "https://mattermost.com/security-updates"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-863" ],
"severity" : "MODERATE",
"github_reviewed" : true,
"github_reviewed_at" : "2025-03-21T22:37:03Z",
"nvd_published_at" : "2025-03-21T09:15:13Z"
}
}