CVE-2026-3787

UltraVNC Windows Service cryptbase.dll uncontrolled search path

Published: Mar 8, 2026Updated: Apr 29, 2026 Sources: CVE List NVDCWE-426

7.0HIGH

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:LAttack Vector

Local

AC:HAttack Complexity

High

PR:LPrivileges Required

Low

UI:NUser Interaction

None

Scope

S:UScope

Unchanged

Impact

C:HConfidentiality

High

I:HIntegrity

High

A:HAvailability

High

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Weaknesses

CWE-426 CWE-427

Affected Products

uvnc

commercial

ultravncOn-prem

Consumer Software / file-utility

and 1 more affected products View all →

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

1 technique

Persistence

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References

https://drive.google.com/file/d/14ixv_1i4D2VrZWyl4RKsvFcN1AMF_qNx/view

drive.google.com

https://vuldb.com/?ctiid.349754

vuldb.com

https://vuldb.com/?id.349754

vuldb.com

and 1 more references View all →

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