CVE-2017-18897: Github.com/mattermost/mattermost server Mattermost Server Mishandles Redirect Denial Vulnerability

MODERATE
Advisory Identifier: GHSA-f7c3-7vp3-44p6
CVSS 6.1
CWE-601
Published
Advisory Summary

CVE-2017-18897 is a MODERATE (CVSS 6.1) mattermost server mishandles redirect denial vulnerability (CWE-601: URL Redirection to Untrusted Site ('Open Redirect')) affecting Github.com/mattermost/mattermost server libraries in the Go ecosystem. The issue involves mattermost server mishandles redirect denial action. Remediation is available by upgrading affected packages to version 4.0.5, 4.1.1, 4.2.0.

CVE-2017-18897 at a Glance

CVE Identifier CVE-2017-18897
GHSA Identifier GHSA-f7c3-7vp3-44p6
Severity MODERATE
CVSS v3.1 Base Score 6.1
CWE Classification CWE-601: URL Redirection to Untrusted Site ('Open Redirect')
Affected Product Github.com/mattermost/mattermost server
Package Ecosystem Go
Published Date
Last Updated

Security Impact

CVSS: 6.1

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

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

How to Fix CVE-2017-18897

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: 4.0.5
Upgrade github.com/mattermost/mattermost-server to 4.0.5
github.com/mattermost/mattermost-server fixed: 4.1.1
Upgrade github.com/mattermost/mattermost-server to 4.1.1
github.com/mattermost/mattermost-server fixed: 4.2.0
Upgrade github.com/mattermost/mattermost-server to 4.2.0
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-2017-18897, 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 4.0.5), 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-601: URL Redirection to Untrusted Site ('Open Redirect'), where the web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect. 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

An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. It mishandles a deny action for a redirection.

CVE-2017-18897 Affected Github.com/mattermost/mattermost server Versions

3 component(s)
Fixed Versions:
4.0.54.1.14.2.0
Product / Package Ecosystem Affected Versions Fixed Version
github.com/mattermost/mattermost-server
Go
< 4.0.5
4.0.5
github.com/mattermost/mattermost-server
Go
≥ 4.1.0
< 4.1.1
4.1.1
github.com/mattermost/mattermost-server
Go
≥ 4.2.0-rc1
< 4.2.0
4.2.0

References

Frequently Asked Questions

What is CVE-2017-18897?
CVE-2017-18897 is a security vulnerability in Github.com/mattermost/mattermost server involving Mattermost Server mishandles redirect denial action under CWE-601: URL Redirection to Untrusted Site ('Open Redirect').
Which Github.com/mattermost/mattermost server versions are affected?
Affected versions include releases prior to 4.0.5, 4.1.1, 4.2.0 across affected packages: github.com/mattermost/mattermost-server.
What version fixes CVE-2017-18897?
Upgrading to 4.0.5, 4.1.1, 4.2.0 (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 4.0.5, 4.1.1, 4.2.0. Upgrade your dependency to 4.0.5, 4.1.1, 4.2.0 or later.
What is the CVSS score of CVE-2017-18897?
CVE-2017-18897 has a CVSS v3.1 base score of 6.1 (MODERATE) with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N.
What CWE is associated with CVE-2017-18897?
CVE-2017-18897 is classified under CWE-601: URL Redirection to Untrusted Site ('Open Redirect') (The web application accepts a user-controlled input that specifies a link to an external site, and uses that link in a redirect.).
How can I check Go dependencies for CVE-2017-18897?
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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f7c3-7vp3-44p6",
  "modified" : "2026-01-12T19:27:05Z",
  "published" : "2022-05-24T17:21:05Z",
  "aliases" : [ "CVE-2017-18897" ],
  "summary" : "Mattermost Server mishandles redirect denial action",
  "details" : "An issue was discovered in Mattermost Server before 4.2.0, 4.1.1, and 4.0.5, when used as an OAuth 2.0 service provider. It mishandles a deny action for a redirection.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "4.0.5"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.1.0"
      }, {
        "fixed" : "4.1.1"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "Go",
      "name" : "github.com/mattermost/mattermost-server"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "4.2.0-rc1"
      }, {
        "fixed" : "4.2.0"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2017-18897"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/3c34e2b2dcb0fde96a10e68d877aa7d0ab511669"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/722fb1947a2e7395ccf16adce9206736d803a9f3"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/mattermost/mattermost/commit/d38328976e2c8bb0fab91e656042a0d8ac37bc76"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/mattermost/mattermost"
  }, {
    "type" : "WEB",
    "url" : "https://mattermost.com/security-updates"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-601" ],
    "severity" : "MODERATE",
    "github_reviewed" : true,
    "github_reviewed_at" : "2026-01-12T19:27:05Z",
    "nvd_published_at" : "2020-06-19T19:15:00Z"
  }
}