CVE catalog
CVE-2026-7839
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 repeate
- Severity
- Critical · CVSS 9.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:N - Published
- Source
- [NVD] · [CVE record]
- EPSS
- 0.66% · Oct 25, 2026
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.
Vulnerable and fixed packages
Distribution-reported package versions and fixes. These do not depend on matching against the OpenFactory package catalog.
| Distribution | Package | Release | Version | Status |
|---|---|---|---|---|
| Cpe | ultravnc | Not reported | Not reported | unknown |
| Cpe | ultravnc | Not reported | Not reported | unknown |
Fixed-version evidence
OpenFactory catalog packages
No matching packages in this catalog.
Observed:
References
- [https://github.com/ultravnc/UltraVNC]
- [https://nvd.nist.gov/vuln/detail/CVE-2026-7839]
- [https://uvnc.com/]
- [https://wid.cert-bund.de/.well-known/csaf/white/2026/wid-sec-w-2026-2162.json]
- [https://www.securin.io/zero-days/cve-2026-7839-hardcoded-default-admin-password-adminadmi2-ultravnc-repeater]
[CERT-Bund public advisories] · [FIRST EPSS] · [National Vulnerability Database (NVD)]