CVE-2026-7184: Github.com/mattermost/mattermost server Mattermost Doesn't Sanitize The Remote Vulnerability

MODERATE
Advisory Identifier: GHSA-9p44-r552-4wp9
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CVSS 6.5
CWE-201
Published
Advisory Summary

CVE-2026-7184 is a MODERATE (CVSS 6.5) mattermost doesn't sanitize the remote vulnerability (CWE-201: Insertion of Sensitive Information Into Sent Data) affecting Github.com/mattermost/mattermost server libraries in the Go ecosystem. The issue involves mattermost doesn't sanitize the remote cluster api response on patch operations. Remediation is available by upgrading affected packages to version 11.6.1, 11.5.5, 10.11.16, 8.0.0-20260428142921-bd8fc9222672.

CVE-2026-7184 at a Glance

CVE Identifier CVE-2026-7184
GHSA Identifier GHSA-9p44-r552-4wp9
Severity MODERATE
CVSS v3.1 Base Score 6.5
CWE Classification CWE-201: Insertion of Sensitive Information Into Sent Data
Affected Product Github.com/mattermost/mattermost server
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 6.5

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:H/I:N/A:N).

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

How to Fix CVE-2026-7184

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: 11.6.1 
Upgrade github.com/mattermost/mattermost-server to 11.6.1
github.com/mattermost/mattermost-server fixed: 11.5.5 
Upgrade github.com/mattermost/mattermost-server to 11.5.5
github.com/mattermost/mattermost-server fixed: 10.11.16 
Upgrade github.com/mattermost/mattermost-server to 10.11.16
github.com/mattermost/mattermost/server/v8 fixed: 8.0.0-20260428142921-bd8fc9222672 
Upgrade github.com/mattermost/mattermost/server/v8 to 8.0.0-20260428142921-bd8fc9222672
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-2026-7184, 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 11.6.1), 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-201: Insertion of Sensitive Information Into Sent Data, where the code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor. 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 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15 fail to sanitize the Remote Cluster API response on PATCH operations, which allows authenticated users with the {{manage_secure_connections}} permission to obtain remote cluster authentication tokens via a PATCH request to the remote cluster endpoint. Mattermost Advisory ID: MMSA-2026-00662

CVE-2026-7184 Affected Github.com/mattermost/mattermost server Versions

4 component(s)
Fixed Versions:
11.6.111.5.510.11.168.0.0-20260428142921-bd8fc9222672
Product / Package Ecosystem Affected Versions Fixed Version
github.com/mattermost/mattermost-server
golang/github.com/mattermost/mattermost-server
Go
≥ 11.6.0
< 11.6.1
All 1 versions
11.6.0
11.6.1
github.com/mattermost/mattermost-server
golang/github.com/mattermost/mattermost-server
Go
≥ 11.5.0
< 11.5.5
11.5.5
github.com/mattermost/mattermost-server
golang/github.com/mattermost/mattermost-server
Go
≥ 10.11.0
< 10.11.16
10.11.16
github.com/mattermost/mattermost/server/v8
golang/github.com/mattermost/mattermost/server/v8
Go
≥ 8.0.0-20250731163400-5b955468ea1e
< 8.0.0-20260428142921-bd8fc9222672
8.0.0-20260428142921-bd8fc9222672

References

NVD — CVE-2026-7184 NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-7184
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost/pull/36313
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost/pull/36311
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost/pull/36310
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost/pull/36306
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost/pull/36288
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/cad3e8e51a4d8627af6442f9df8ae3667fac7fc1
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/c5e67e28271c23cb585fe1a30ae81defcde848d6
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/bd8fc92226726da06c8fabaef568cc9ebaee1cb8
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/6fd49f56b5920569218fd2fc76d8ae802942f274
Security Fix Commit FIX COMMIT
https://github.com/mattermost/mattermost/commit/1a0643df00c1f51a3b7e919eec034eaf955f612f
Github.com/mattermost/mattermost server Release RELEASE
https://github.com/mattermost/mattermost/releases/tag/v10.11.16
Github.com/mattermost/mattermost server Release RELEASE
https://github.com/mattermost/mattermost/releases/tag/v11.5.5
Github.com/mattermost/mattermost server Release RELEASE
https://github.com/mattermost/mattermost/releases/tag/v11.6.2
Github.com/mattermost/mattermost server Release RELEASE
https://github.com/mattermost/mattermost/releases/tag/v11.7.0
Github.com/mattermost/mattermost server Security Information SECURITY
https://mattermost.com/security-updates
Github.com/mattermost/mattermost server Source Repository REPOSITORY
https://github.com/mattermost/mattermost

Frequently Asked Questions

What is CVE-2026-7184?
CVE-2026-7184 is a security vulnerability in Github.com/mattermost/mattermost server involving Mattermost doesn't sanitize the Remote Cluster API response on PATCH operations under CWE-201: Insertion of Sensitive Information Into Sent Data.
Which Github.com/mattermost/mattermost server versions are affected?
Affected versions include releases prior to 11.6.1, 11.5.5, 10.11.16, 8.0.0-20260428142921-bd8fc9222672 across affected packages: github.com/mattermost/mattermost-server, github.com/mattermost/mattermost/server/v8.
What version fixes CVE-2026-7184?
Upgrading to 11.6.1, 11.5.5, 10.11.16, 8.0.0-20260428142921-bd8fc9222672 (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 11.6.1, 11.5.5, 10.11.16. Upgrade your dependency to 11.6.1, 11.5.5, 10.11.16 or later.
Is github.com/mattermost/mattermost/server/v8 affected?
Yes, github.com/mattermost/mattermost/server/v8 is affected in releases prior to 8.0.0-20260428142921-bd8fc9222672. Upgrade your dependency to 8.0.0-20260428142921-bd8fc9222672 or later.
What is the CVSS score of CVE-2026-7184?
CVE-2026-7184 has a CVSS v3.1 base score of 6.5 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N.
What CWE is associated with CVE-2026-7184?
CVE-2026-7184 is classified under CWE-201: Insertion of Sensitive Information Into Sent Data (The code transmits data to another actor, but a portion of the data includes sensitive information that should not be accessible to that actor.).
How can I check Go dependencies for CVE-2026-7184?
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-9p44-r552-4wp9",
  "modified" : "2026-08-24T21:48:36Z",
  "published" : "2026-06-12T18:31:59Z",
  "aliases" : [ "CVE-2026-7184" ],
  "summary" : "Mattermost doesn't sanitize the Remote Cluster API response on PATCH operations",
  "details" : "Mattermost versions 11.6.x <= 11.6.1, 11.5.x <= 11.5.4, 10.11.x <= 10.11.15 fail to sanitize the Remote Cluster API response on PATCH operations, which allows authenticated users with the {{manage_secure_connections}} permission to obtain remote cluster authentication tokens via a PATCH request to the remote cluster endpoint. Mattermost Advisory ID: MMSA-2026-00662",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:N/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.6.0"
      }, {
        "fixed" : "11.6.1"
      } ]
    } ],
    "versions" : [ "11.6.0" ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "11.5.0"
      }, {
        "fixed" : "11.5.5"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 11.5.4"
    }
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "10.11.0"
      }, {
        "fixed" : "10.11.16"
      } ]
    } ],
    "database_specific" : {
      "last_known_affected_version_range" : "<= 10.11.15"
    }
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost/server/v8"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "8.0.0-20250731163400-5b955468ea1e"
      }, {
        "fixed" : "8.0.0-20260428142921-bd8fc9222672"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2026-7184"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/pull/36313"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/pull/36311"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/pull/36310"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/pull/36306"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/pull/36288"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/cad3e8e51a4d8627af6442f9df8ae3667fac7fc1"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/c5e67e28271c23cb585fe1a30ae81defcde848d6"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/bd8fc92226726da06c8fabaef568cc9ebaee1cb8"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/6fd49f56b5920569218fd2fc76d8ae802942f274"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/1a0643df00c1f51a3b7e919eec034eaf955f612f"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/releases/tag/v10.11.16"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/releases/tag/v11.5.5"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/releases/tag/v11.6.2"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/releases/tag/v11.7.0"
  }, {
    "type" : "WEB",
    "url" : "https://mattermost.com/security-updates"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/mattermost/mattermost"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-201" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-08-24T21:48:36Z",
    "nvd_published_at" : "2026-06-12T17:16:27Z"
  }
}