CVE-2026-3787

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.

CVSS v3 7.0 HIGH
CVSS v2.0 6.0 MEDIUM

7.0^/10

CVSS v3 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.0^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:H/Au:S/C:C/I:C/A:C

Exploitability : 1.5 / Impact : 10.0

Access Vector LOCAL

Access Complexity HIGH

Authentication SINGLE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://drive.google.com/file/d/14ixv_1i4D2VrZWyl4RKsvFcN1AMF_qNx/view	Permissions Required
https://vuldb.com/?ctiid.349754	Permissions Required VDB Entry
https://vuldb.com/?id.349754	Third Party Advisory VDB Entry
https://vuldb.com/?submit.767257	Third Party Advisory VDB Entry

Configurations

Configuration 1 (hide)

AND

cpe:2.3:a:uvnc:ultravnc:1.6.4.0:*:*:*:*:*:*:*

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*

History

No history.

Information

Published : 2026-03-08 23:15

Updated : 2026-03-10 18:51

NVD link : CVE-2026-3787

Mitre link : CVE-2026-3787

CVE.ORG link : CVE-2026-3787

JSON object : View

Products Affected

microsoft

windows

uvnc

ultravnc

CWE

CWE-426

Untrusted Search Path

CWE-427

Uncontrolled Search Path Element

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