CVE-2026-59104
UgCS server HCI authentication bypass with empty credentials
UgCS server before 6.2 contains an authentication bypass in the HCI protocol login handler (LoginHandler) exposed on TCP port 3334. When the user database contains exactly one user (the default single-operator installation), a LoginRequest with empty userLogin and userPassword fields is interpreted as \"use the only user\" rather than as invalid credentials, and the server returns a fully authenticated session. Because the service listens on all interfaces (0.0.0.0) without TLS by default, an unauthenticated remote attacker with network access to port 3334 can obtain an authenticated session without knowing any credential and then issue privileged commands, including commanding connected drones and uploading flight routes.
Fixes and workarounds
Fix
Upgrade to UgCS 6.2 or later, in which empty credentials are no longer accepted as a valid login.
Source: CNA: ENISAWorkaround
For deployments that cannot upgrade immediately: bind the HCI listener to 127.0.0.1, restrict TCP port 3334 with host and network firewall rules, and place the service behind an authenticated TLS transport.
Source: CNA: ENISAAffected products and versions
| Product | Versions | Authority |
|---|---|---|
| UgCS SPH Engineering Platforms: Windows, MacOS, Linux |
≥ 0; < 6.2 (affected, custom)
Other versions: unaffected |
CNA: ENISA |
Version ranges are source assertions. Check the vendor advisory and your installed configuration before determining exposure.
CVSS assessments
| Version / score | Vector | Authority |
|---|---|---|
| 4.0 / 9.3 critical |
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N | CNA: ENISA |
| 3.1 / 9.8 critical |
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H | CNA: ENISA |
Exploit evidence
No exploit evidence in collected sources. This is not proof of no exploitation.
References
- https://www.ugcs.com/CNA: ENISA · product
- https://offseq.com/en/research/ugcs-cve-2026-59104/CNA: ENISA · third-party-advisory
For agents and automation
Read public disclosures for free as Markdown or JSON. Compatible browsers also expose native WebMCP tools to search disclosures, read this page, and discover API access.
Use the ontology-linked Cyber API with x402 pay per request, or a Y2 Pro or Elite API key with the intel:cyber scope.
Endpoints and access details
https://api.y2.dev/api/v2/cyber/cveshttps://api.y2.dev/api/v2/cyber/cves/{cveId}
A workspace owner or admin can create a Pro or Elite API key. Send Authorization: Bearer <Y2_API_KEY> from your trusted agent runtime.
For x402, omit Authorization and read the HTTP 402 payment challenge before signing a retry. Public browser tools do not make payments.