CVE-2025-11777: Github.com/mattermost/mattermost server Mattermost Incorrect Authorization Vulnerability Vulnerability

LOW
Advisory Identifier: GHSA-mqcj-8c2g-h97q
Share
CVSS 3.1
CWE-863
Published
Advisory Summary

CVE-2025-11777 is a LOW (CVSS 3.1) mattermost incorrect authorization vulnerability vulnerability (CWE-863: Incorrect Authorization) affecting Github.com/mattermost/mattermost server libraries in the Go ecosystem. The issue involves mattermost incorrect authorization vulnerability. Remediation is available by upgrading affected packages to version 10.11.4, 10.5.12, 8.0.0-20250905150616-ba86dfc5876b, 5.3.2-0.20250905150616-ba86dfc5876b.

CVE-2025-11777 at a Glance

CVE Identifier CVE-2025-11777
GHSA Identifier GHSA-mqcj-8c2g-h97q
Severity LOW
CVSS v3.1 Base Score 3.1
CWE Classification CWE-863: Incorrect Authorization
Affected Product Github.com/mattermost/mattermost server
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 3.1

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N).

Attack Vector Network (AV:N)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction None (UI:N)
Scope Unchanged (S:U)
Confidentiality Low (C:L)
Integrity None (I:N)
Availability None (A:N)

How to Fix CVE-2025-11777

To remediate this vulnerability, upgrade all affected Github.com/mattermost/mattermost server dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

github.com/mattermost/mattermost-server fixed: 10.11.4 
Upgrade github.com/mattermost/mattermost-server to 10.11.4
github.com/mattermost/mattermost-server fixed: 10.5.12 
Upgrade github.com/mattermost/mattermost-server to 10.5.12
github.com/mattermost/mattermost/server/v8 fixed: 8.0.0-20250905150616-ba86dfc5876b 
Upgrade github.com/mattermost/mattermost/server/v8 to 8.0.0-20250905150616-ba86dfc5876b
github.com/mattermost/mattermost fixed: 5.3.2-0.20250905150616-ba86dfc5876b 
Upgrade github.com/mattermost/mattermost to 5.3.2-0.20250905150616-ba86dfc5876b
github.com/mattermost/mattermost-server fixed: 5.3.2-0.20250905150616-ba86dfc5876b 
Upgrade github.com/mattermost/mattermost-server to 5.3.2-0.20250905150616-ba86dfc5876b
github.com/mattermost/mattermost-server/v5 fixed: 5.3.2-0.20250905150616-ba86dfc5876b 
Upgrade github.com/mattermost/mattermost-server/v5 to 5.3.2-0.20250905150616-ba86dfc5876b
github.com/mattermost/mattermost-server/v6 fixed: 5.3.2-0.20250905150616-ba86dfc5876b 
Upgrade github.com/mattermost/mattermost-server/v6 to 5.3.2-0.20250905150616-ba86dfc5876b
Verify Direct and Transitive Dependencies

Run 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

How to Check if You Are Affected

To determine whether your application is affected by CVE-2025-11777, inspect your project dependencies for Github.com/mattermost/mattermost server:

inspect dependencies for github.com/mattermost/mattermost-server

Analyze the terminal output to locate any version of Github.com/mattermost/mattermost server in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 10.11.4), 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, 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

Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API, which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint.

CVE-2025-11777 Affected Github.com/mattermost/mattermost server Versions

7 component(s)
Fixed Versions:
10.11.410.5.128.0.0-20250905150616-ba86dfc5876b5.3.2-0.20250905150616-ba86dfc5876b
Product / Package Ecosystem Affected Versions Fixed Version
github.com/mattermost/mattermost-server
golang/github.com/mattermost/mattermost-server
Go
≥ 10.11.0
< 10.11.4
10.11.4
github.com/mattermost/mattermost-server
golang/github.com/mattermost/mattermost-server
Go
≥ 10.5.0
< 10.5.12
10.5.12
github.com/mattermost/mattermost/server/v8
golang/github.com/mattermost/mattermost/server/v8
Go
< 8.0.0-20250905150616-ba86dfc5876b
8.0.0-20250905150616-ba86dfc5876b
github.com/mattermost/mattermost
golang/github.com/mattermost/mattermost
Go
< 5.3.2-0.20250905150616-ba86dfc5876b
5.3.2-0.20250905150616-ba86dfc5876b
github.com/mattermost/mattermost-server
golang/github.com/mattermost/mattermost-server
Go
< 5.3.2-0.20250905150616-ba86dfc5876b
5.3.2-0.20250905150616-ba86dfc5876b
github.com/mattermost/mattermost-server/v5
golang/github.com/mattermost/mattermost-server/v5
Go
< 5.3.2-0.20250905150616-ba86dfc5876b
5.3.2-0.20250905150616-ba86dfc5876b
github.com/mattermost/mattermost-server/v6
golang/github.com/mattermost/mattermost-server/v6
Go
< 5.3.2-0.20250905150616-ba86dfc5876b
5.3.2-0.20250905150616-ba86dfc5876b

References

NVD — CVE-2025-11777 NVD
https://nvd.nist.gov/vuln/detail/CVE-2025-11777
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/98acefe911dd9de7edf47a7d825dd99f53141a52
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/ba86dfc5876b354b9d3c20ff45c08ca6f8426149
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/d72d437f1567ba0b639b6e4fd73bab06c51baab5
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost
Github.com/mattermost/mattermost server Security Information SECURITY
https://mattermost.com/security-updates

Frequently Asked Questions

What is CVE-2025-11777?
CVE-2025-11777 is a security vulnerability in Github.com/mattermost/mattermost server involving Mattermost Incorrect Authorization vulnerability under CWE-863: Incorrect Authorization.
Which Github.com/mattermost/mattermost server versions are affected?
Affected versions include releases prior to 10.11.4, 10.5.12, 8.0.0-20250905150616-ba86dfc5876b, 5.3.2-0.20250905150616-ba86dfc5876b across affected packages: github.com/mattermost/mattermost-server, github.com/mattermost/mattermost/server/v8, github.com/mattermost/mattermost, github.com/mattermost/mattermost-server/v5, github.com/mattermost/mattermost-server/v6.
What version fixes CVE-2025-11777?
Upgrading to 10.11.4, 10.5.12, 8.0.0-20250905150616-ba86dfc5876b, 5.3.2-0.20250905150616-ba86dfc5876b (or the latest patched release for your respective branch) resolves the vulnerability.
Is github.com/mattermost/mattermost-server affected?
Yes, github.com/mattermost/mattermost-server is affected in releases prior to 10.11.4, 10.5.12, 5.3.2-0.20250905150616-ba86dfc5876b. Upgrade your dependency to 10.11.4, 10.5.12, 5.3.2-0.20250905150616-ba86dfc5876b or later.
Is github.com/mattermost/mattermost/server/v8 affected?
Yes, github.com/mattermost/mattermost/server/v8 is affected in releases prior to 8.0.0-20250905150616-ba86dfc5876b. Upgrade your dependency to 8.0.0-20250905150616-ba86dfc5876b or later.
What is the CVSS score of CVE-2025-11777?
CVE-2025-11777 has a CVSS v3.1 base score of 3.1 (LOW) with vector string CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N.
What CWE is associated with CVE-2025-11777?
CVE-2025-11777 is classified under CWE-863: Incorrect Authorization (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.).
How can I check Go dependencies for CVE-2025-11777?
Run the dependency tree command: 'inspect dependencies for github.com/mattermost/mattermost-server'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-mqcj-8c2g-h97q",
  "modified" : "2025-11-14T15:54:51Z",
  "published" : "2025-11-13T18:31:05Z",
  "aliases" : [ "CVE-2025-11777" ],
  "summary" : "Mattermost Incorrect Authorization vulnerability",
  "details" : "Mattermost versions 10.11.x <= 10.11.3, 10.5.x <= 10.5.11 fail to properly validate team membership permissions in the Add Channel Member API, which allows users from one team to access user metadata and channel membership information from other teams via the API endpoint.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:L/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.11.0"
      }, {
        "fixed" : "10.11.4"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.5.0"
      }, {
        "fixed" : "10.5.12"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost/server/v8"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "8.0.0-20250905150616-ba86dfc5876b"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "5.3.2-0.20250905150616-ba86dfc5876b"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "5.3.2-0.20250905150616-ba86dfc5876b"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server/v5"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "5.3.2-0.20250905150616-ba86dfc5876b"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server/v6"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "5.3.2-0.20250905150616-ba86dfc5876b"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2025-11777"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/98acefe911dd9de7edf47a7d825dd99f53141a52"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/ba86dfc5876b354b9d3c20ff45c08ca6f8426149"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/d72d437f1567ba0b639b6e4fd73bab06c51baab5"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/mattermost/mattermost"
  }, {
    "type" : "WEB",
    "url" : "https://mattermost.com/security-updates"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-863" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2025-11-14T15:54:50Z",
    "nvd_published_at" : "2025-11-13T18:15:49Z"
  }
}