{"schemaVersion":3,"id":"CVE-2026-7839","aliases":[],"status":"published","duplicateOf":null,"title":null,"description":"UltraVNC repeater through 1.8.2.2 initializes the HTTP administration server with a hardcoded default password. In repeater/webgui/settings.c:197, when settings2.txt is absent on first run the repeater writes the literal string \"adminadmi2\" as the admin password via strcpy_s(saved_password, 64, \"adminadmi2\"). The HTTP Basic-auth handler wi_decode_auth() checks this password without rate-limiting or lockout. Any remote attacker who can reach the repeater HTTP port (default TCP 80) can authenticate as administrator using the well-known default credential on a fresh or unmodified installation, gaining full control of the repeater configuration including allow/deny rules and session visibility.","dates":{"published":"2026-07-01T03:33:27.724Z","modified":"2026-07-09T04:35:44.027Z","reserved":null,"kevAdded":[],"kevDue":[]},"cvss":{"headline":{"score":9.1,"severity":"critical","version":"3.1","versionLabel":"v3.1","source":"CVE.org","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","computed":false,"selection":"backend-summary"},"metrics":[{"version":"3.1","versionLabel":"v3.1","source":"CVE.org","score":9.1,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","exploitability":null,"impact":null,"computed":false},{"version":"3.1","versionLabel":"v3.1","source":"NVD","score":9.1,"severity":"critical","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N","exploitability":null,"impact":null,"computed":false}]},"epss":{"probability":0.00655,"percentile":0.50489,"severity":"low","asOf":"2026-10-20T00:00:00.000Z","change":{"pp":0,"baselineDate":"2026-09-20T00:00:00.000Z","baselineScore":0.00655},"history":[{"date":"2026-09-14T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-15T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-16T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-17T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-18T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-19T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-20T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-10T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-11T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-12T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-13T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-14T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-15T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-16T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-17T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-18T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-19T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-20T00:00:00.000Z","score":0.00655,"percentile":0.50489}],"last30":[{"date":"2026-09-20T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-21T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-22T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-23T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-24T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-25T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-26T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-27T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-28T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-29T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-09-30T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-01T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-02T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-03T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-04T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-05T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-06T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-07T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-08T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-09T00:00:00.000Z","score":0.00655,"percentile":null},{"date":"2026-10-10T00:00:00.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