{"schemaVersion":3,"id":"CVE-2026-19600","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"Mattermost versions 11.9.x <= 11.9.1, 11.8.x <= 11.8.5, 11.7.x <= 11.7.10, 11.10.x <= 11.10.1 fail to sanitize authentication tokens before writing them to server log entries, which allows an attacker with access to server logs to obtain valid session tokens or OAuth access tokens and impersonate authenticated users via the debug-level Mattermost server log.. Mattermost Advisory ID: MMSA-2026-00763","dates":{"published":"2026-10-16T07:07:17.899Z","modified":"2026-10-16T12:02:51.761Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":4.5,"severity":"medium","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":4.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":4.5,"severity":"medium","vector":"CVSS:3.1/AV:N/AC:L/PR:H/UI:R/S:U/C:H/I:N/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00236,"percentile":0.13739,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":null,"baselineDate":null,"baselineScore":null},"history":[{"date":"2026-10-16T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00236,"percentile":0.13739}],"last30":[{"date":"2026-10-16T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00236,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00236,"percentile":0.13739}]},"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-532","name":"Insertion of Sensitive Information into Log File","description":"The product writes sensitive information to a log file.","type":"weakness","status":"Incomplete","abstraction":"Base","likelihoodOfExploit":"Medium","url":"https://cwe.mitre.org/data/definitions/532.html"}],"affected":[{"vendor":"mattermost","product":"mattermost","name":"Mattermost","label":"mattermost","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≥ 11.9.0, ≤ 11.9.1","noFixRecorded":false,"fixedIn":null},{"text":"≥ 11.8.0, ≤ 11.8.5","noFixRecorded":false,"fixedIn":null},{"text":"≥ 11.7.0, ≤ 11.7.10","noFixRecorded":false,"fixedIn":null},{"text":"≥ 11.10.0, ≤ 11.10.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"≥ 11.9.0, ≤ 11.9.1 | ≥ 11.8.0, ≤ 11.8.5 | ≥ 11.7.0, ≤ 11.7.10 | ≥ 11.10.0, ≤ 11.10.1","eol":null,"hubHref":"/vendor/mattermost/mattermost"}],"affectedCount":1,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://mattermost.com/security-updates","label":"mattermost.com/security-updates","hostname":"mattermost.com","tags":["Vendor Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-10-16T07:07:17.899Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-10-16T12:02:51.761Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":18,"level":"low","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T22:45:05.964Z","stale":false,"partial":false}}