cvedb.io
CVE-2026-7839
CRITICAL · CVSS 9.1
EPSS exploitation probability: 0%
Published 2026-07-01T05:16:24.680 · Last modified 2026-07-02T15:30:15.090

Summary

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.

Affected products

uvnc — ultravnc

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.