CVE-2026-7839: uvnc UltraVNC, заобикаляне на вход и права

Описание

Оригинално описание

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.

Засегнати продукти

• uvnc UltraVNC: до 1.8.2.2

Вид слабост

• CWE-798 Use of Hard-coded Credentials

История

Други уязвимости в uvnc UltraVNC

• 9.8CVE-2026-7840
• 8.8CVE-2026-7838
• 7.5CVE-2026-7831
• 7.4CVE-2026-7830
• 7.2CVE-2026-7829

Първоизточници

• https://www.cve.org/CVERecord?id=CVE-2026-7839
• https://nvd.nist.gov/vuln/detail/CVE-2026-7839
• https://uvnc.com/
• https://github.com/ultravnc/UltraVNC
• https://www.securin.io/zero-days/cve-2026-7839-hardcoded-default-admin-password-adminadmi2-ultravnc-repeater