A weakness has been identified in UltraVNC 1.6.4.0 on Windows. This affects an unknown function in the library cryptbase.dll of the component Windows Service. This manipulation causes uncontrolled search path. The attack requires local access. A high degree of complexity is needed for the attack. The exploitability is reported as difficult. The vendor was contacted early about this disclosure but did not respond in any way.
History

Sun, 08 Mar 2026 23:15:00 +0000

Type Values Removed Values Added
Description A weakness has been identified in UltraVNC 1.6.4.0 on Windows. This affects an unknown function in the library cryptbase.dll of the component Windows Service. This manipulation causes uncontrolled search path. The attack requires local access. A high degree of complexity is needed for the attack. The exploitability is reported as difficult. The vendor was contacted early about this disclosure but did not respond in any way.
Title UltraVNC Windows Service cryptbase.dll uncontrolled search path
First Time appeared Ultravnc
Ultravnc ultravnc
Weaknesses CWE-426
CWE-427
CPEs cpe:2.3:a:ultravnc:ultravnc:*:*:*:*:*:*:*:*
Vendors & Products Ultravnc
Ultravnc ultravnc
References
Metrics cvssV2_0

{'score': 6, 'vector': 'AV:L/AC:H/Au:S/C:C/I:C/A:C/E:POC/RL:ND/RC:UR'}

cvssV3_0

{'score': 7, 'vector': 'CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R'}

cvssV3_1

{'score': 7, 'vector': 'CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H/E:P/RL:X/RC:R'}

cvssV4_0

{'score': 7.3, 'vector': 'CVSS:4.0/AV:L/AC:H/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P'}


cve-icon MITRE

Status: PUBLISHED

Assigner: VulDB

Published: 2026-03-08T23:02:06.940Z

Updated: 2026-03-08T23:02:06.940Z

Reserved: 2026-03-08T07:11:28.250Z

Link: CVE-2026-3787

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Awaiting Analysis

Published: 2026-03-08T23:15:50.690

Modified: 2026-03-09T13:35:07.393

Link: CVE-2026-3787

cve-icon Redhat

No data.