CVE-2017-18884: Github.com/mattermost/mattermost server Mattermost Server Exposes OAuth Personal Vulnerability
CRITICALCVE-2017-18884 is a CRITICAL mattermost server exposes oauth personal vulnerability (CWE-269: Improper Privilege Management) affecting Github.com/mattermost/mattermost server libraries in the Go ecosystem. The issue involves mattermost server exposes oauth personal access tokens to attackers. Remediation is available by upgrading affected packages to version 4.1.2, 4.2.1, 4.3.0.
CVE-2017-18884 at a Glance
How to Fix CVE-2017-18884
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.
Upgrade github.com/mattermost/mattermost-server to 4.1.2Upgrade github.com/mattermost/mattermost-server to 4.2.1Upgrade github.com/mattermost/mattermost-server to 4.3.0Run the following command in your project directory to verify that all resolved dependencies use the patched release:
inspect dependencies for github.com/mattermost/mattermost-serverHow to Check if You Are Affected
To determine whether your application is affected by CVE-2017-18884, inspect your project dependencies for Github.com/mattermost/mattermost server:
inspect dependencies for github.com/mattermost/mattermost-serverAnalyze 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 4.1.2), 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-269: Improper Privilege Management, where the product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for 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
CVE-2017-18884 Affected Github.com/mattermost/mattermost server Versions
3 component(s)| Product / Package | Ecosystem | Affected Versions | Fixed Version |
|---|---|---|---|
|
github.com/mattermost/mattermost-server
|
Go |
< 4.1.2
|
4.1.2
|
|
github.com/mattermost/mattermost-server
|
Go |
≥ 4.2.0-rc1
< 4.2.1
|
4.2.1
|
|
github.com/mattermost/mattermost-server
|
Go |
≥ 4.3.0-rc1
< 4.3.0
|
4.3.0
|
References
Frequently Asked Questions
What is CVE-2017-18884?
Which Github.com/mattermost/mattermost server versions are affected?
What version fixes CVE-2017-18884?
Is github.com/mattermost/mattermost-server affected?
What CWE is associated with CVE-2017-18884?
How can I check Go dependencies for CVE-2017-18884?
Machine-readable OSV JSON
OSV v1.5 Schema
{
"schema_version" : "1.4.0",
"id" : "GHSA-876j-jfqf-m7j7",
"modified" : "2025-12-05T19:38:03Z",
"published" : "2022-05-24T17:21:04Z",
"aliases" : [ "CVE-2017-18884" ],
"summary" : "Mattermost Server exposes OAuth personal access tokens to attackers",
"details" : "An issue was discovered in Mattermost Server before 4.3.0, 4.2.1, and 4.1.2. It allows attackers to gain privileges by using a registered OAuth application with personal access tokens.",
"severity" : [ {
"type" : "CVSS_V4",
"score" : "CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N"
} ],
"affected" : [ {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "0"
}, {
"fixed" : "4.1.2"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.2.0-rc1"
}, {
"fixed" : "4.2.1"
} ]
} ]
}, {
"package" : {
"ecosystem" : "Go",
"name" : "github.com/mattermost/mattermost-server"
},
"ranges" : [ {
"type" : "ECOSYSTEM",
"events" : [ {
"introduced" : "4.3.0-rc1"
}, {
"fixed" : "4.3.0"
} ]
} ]
} ],
"references" : [ {
"type" : "ADVISORY",
"url" : "https://nvd.nist.gov/vuln/detail/CVE-2017-18884"
}, {
"type" : "WEB",
"url" : "https://mattermost.com/security-updates"
} ],
"database_specific" : {
"cwe_ids" : [ "CWE-269", "CWE-863" ],
"severity" : "CRITICAL",
"github_reviewed" : true,
"github_reviewed_at" : "2025-12-05T19:38:03Z",
"nvd_published_at" : "2020-06-19T19:15:00Z"
}
}