{"schemaVersion":3,"id":"CVE-2026-82845","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"The Masteriyo LMS  WordPress plugin before 3.4.1 does not prevent user-supplied values held as metadata from being deserialized when they are read back, allowing users with a minimal account to inject arbitrary PHP objects and, by way of a class shipped in a library bundled with the Masteriyo LMS  WordPress plugin before 3.4.1, write and execute arbitrary code on the server. A weaker form of the same issue is reachable without an account and yields an arbitrary file write rather than code execution.","dates":{"published":"2026-09-12T06:00:09.956Z","modified":"2026-09-12T15:33:08.896Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.9,"severity":"critical","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":9.9,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":9.9,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"wordfence","score":7.5,"severity":"high","vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00638,"percentile":0.4959,"severity":"low","asOf":"2026-10-19T00:00:00.000Z","change":{"pp":0.28400000000000003,"baselineDate":"2026-09-19T00:00:00.000Z","baselineScore":0.00354},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00638,"percentile":0.4959}],"last30":[{"date":"2026-09-19T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00354,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00638,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00638,"percentile":0.4959}]},"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":[{"id":"REF_55E5860128AAF5FC","name":"Exploit Reference (wpscan.com)","source":"reference","url":"https://wpscan.com/vulnerability/5ced30ea-8b78-495f-b10c-42b3f10adcb3/","maturity":"unknown","reliabilityScore":0.2,"verified":false,"type":null,"platforms":[],"requiresAuth":null,"exploitdb":null,"metasploit":null}],"exploitCount":1,"weaknesses":[{"id":"CWE-502","name":"Deserialization of Untrusted Data","description":"The product deserializes untrusted data without sufficiently ensuring that the resulting data will be valid.","type":"weakness","status":"Draft","abstraction":"Base","likelihoodOfExploit":"Medium","url":"https://cwe.mitre.org/data/definitions/502.html"}],"affected":[{"vendor":"unknown","product":"masteriyo lms","name":"Masteriyo LMS","label":"masteriyo lms","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"< 3.4.1","noFixRecorded":false,"fixedIn":null}],"versionsText":"< 3.4.1","eol":null,"hubHref":"/vendor/unknown/masteriyo_lms"},{"vendor":"wordpress","product":"learning-management-system","name":"Masteriyo LMS – LMS Course Builder, Quizzes & Certificates","label":"learning-management-system","ecosystem":null,"cpePart":"a","purl":null,"purlType":null,"versions":[{"text":"≤ 3.4.0 (fixed in 3.4.1)","noFixRecorded":false,"fixedIn":"3.4.1"}],"versionsText":"≤ 3.4.0 (fixed in 3.4.1)","eol":null,"hubHref":null}],"affectedCount":2,"eol":{"hasEol":false,"count":0},"references":[{"url":"https://wpscan.com/vulnerability/5ced30ea-8b78-495f-b10c-42b3f10adcb3/","label":"wpscan.com/vulnerability/5ced30ea-8b78-495f-b10c-42b3f10adcb3/","hostname":"wpscan.com","tags":["Exploit","VDB Entry","Technical Description"]},{"url":"https://www.wordfence.com/threat-intel/vulnerabilities/id/d57816cb-1e73-4097-ae1d-7ae2879a4c5c","label":"www.wordfence.com/threat-intel/vulnerabilities/id/d57816cb-1e73-4097-ae1d-7ae2879a4c5c","hostname":"www.wordfence.com","tags":["Vendor Advisory"]}],"lineage":{"upstream":[],"downstream":[],"duplicates":[],"related":[]},"timeline":[{"kind":"published","date":"2026-09-12T06:00:09.956Z","label":"Published","detail":"Vulnerability first disclosed.","source":null},{"kind":"modified","date":"2026-09-12T15:33:08.896Z","label":"Last modified","detail":"Vulnerability information updated.","source":null}],"risk":{"score":70,"level":"high","profile":"Default","thresholds":{"critical":75,"high":50,"medium":25,"low":10}},"meta":{"dataAsOf":"2026-10-20T04:47:20.350Z","stale":false,"partial":false}}