CVE-2026-7839 (GCVE-0-2026-7839)
Vulnerability from cvelistv5 – Published: 2026-07-01 03:33 – Updated: 2026-07-01 12:32
VLAI?
Title
UltraVNC repeater ships hardcoded default admin password allowing unauthenticated admin access
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.
Severity ?
9.1 (Critical)
CWE
- CWE-798 - Use of Hard-coded Credentials
Assigner
References
| URL | Tags | |||||||
|---|---|---|---|---|---|---|---|---|
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Credits
Arjun Basnet, Securin (arjun.basnet@securin.io)
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Sightings
| Author | Source | Type | Date |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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