{"schemaVersion":3,"id":"CVE-2018-21258","aliases":["GHSA-5mh6-p63g-3mv5","GO-2025-4146"],"status":"published","duplicateOf":null,"title":null,"description":"An issue was discovered in Mattermost Server before 5.1. It allows attackers to cause a denial of service via the invite_people slash command.","dates":{"published":"2020-06-19T16:45:05.000Z","modified":"2024-08-05T12:26:39.589Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":7.5,"severity":"high","version":"3.1","versionLabel":"v3.1","source":"NVD","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","exploitability":null,"impact":null,"computed":false},{"version":"2.0","versionLabel":"v2.0","source":"NVD","score":5,"severity":"medium","vector":"AV:N/AC:L/Au:N/C:N/I:N/A:P","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"OSV · Go","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","exploitability":10,"impact":6,"computed":true}]},"epss":{"probability":0.01165,"percentile":0.66812,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0.010000000000000113,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.01155},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01165,"percentile":0.66812}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.01155,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.01165,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.01165,"percentile":0.66812}]},"kev":{"state":"not-listed","entries":[],"listedCount":0,"totalCatalogs":3,"catalogs":[{"source":"cisa","label":"CISA","listed":false,"entry":null},{"source":"enisa","label":"ENISA","listed":false,"entry":null},{"source":"circl","label":"CIRCL","listed":false,"entry":null}]},"ransomware":{"state":"none-recorded","sources":[]},"exploits":[],"exploitCount":0,"weaknesses":[{"id":"CWE-74","name":"Improper Neutralization of Special Elements in Output Used by a Downstream Component ('Injection')","description":"The product constructs all or part of a command, data structure, or record using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify how it is parsed or interpreted when it is sent to a downstream component.","type":"weakness","status":"Incomplete","abstraction":"Class","likelihoodOfExploit":"High","url":"https://cwe.mitre.org/data/definitions/74.html"}],"affected":[{"vendor":"github.com/mattermost","product":"mattermost-server","name":"github.com/mattermost/mattermost-server","label":"mattermost-server","ecosystem":"Go","cpePart":null,"purl":"pkg:golang/github.com/mattermost/mattermost-server","purlType":"golang","versions":[{"text":"< 5.1.0","noFixRecorded":false,"fixedIn":null},{"text":"All versions","noFixRecorded":true,"fixedIn":null}],"versionsText":"< 5.1.0 | All versions (No fix recorded)","eol":null,"hubHref":null},{"vendor":"github.com/mattermost/mattermost-server","product":"v5","name":"github.com/mattermost/mattermost-server/v5","label":"v5","ecosystem":"Go","cpePart":null,"purl":"pkg:golang/github.com/mattermost/mattermost-server/v5","purlType":"golang","versions":[{"text":"< 5.1.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 5.1.0","eol":null,"hubHref":null},{"vendor":"mattermost","product":"mattermost_server","name":"mattermost server","label":"mattermost_server","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 5.1.0","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 5.1.0","eol":{"isEol":null,"eolDate":null,"matchMethod":"cpe","cycle":null,"product":{"name":"mattermost","label":"Mattermost","category":"server-app"}},"hubHref":"/vendor/mattermost/mattermost_server"}],"affectedCount":3,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://mattermost.com/security-updates/","label":"mattermost.com/security-updates/","hostname":"mattermost.com","tags":["X Refsource CONFIRM","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2018-21258","label":"nvd.nist.gov/vuln/detail/CVE-2018-21258","hostname":"nvd.nist.gov","tags":["Advisory"]},{"url":"https://github.com/mattermost/mattermost/commit/af615ffc24b774d76deef8c93282831432669dd8","label":"github.com/mattermost/mattermost/commit/af615ffc24b774d76deef8c93282831432669dd8","hostname":"github.com","tags":["WEB"]},{"url":"https://github.com/mattermost/mattermost","label":"github.com/mattermost/mattermost","hostname":"github.com","tags":["PACKAGE"]},{"url":"https://mattermost.com/security-updates","label":"mattermost.com/security-updates","hostname":"mattermost.com","tags":["WEB"]},{"url":"https://github.com/advisories/GHSA-5mh6-p63g-3mv5","label":"github.com/advisories/GHSA-5mh6-p63g-3mv5","hostname":"github.com","tags":["Advisory"]}],"lineage":{"upstream":[],"downstream":["OPENSUSE-SU-2026:21483-1","SUSE-SU-2025:4395-1"],"duplicates":[],"related":["OPENSUSE-SU-2026:21483-1","SUSE-SU-2025:4395-1"]},"timeline":[{"kind":"published","date":"2020-06-19T16:45:05.000Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2024-08-05T12:26:39.589Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":30,"level":"medium","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-19T22:40:59.164Z","stale":false,"partial":false}}