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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
NVD MITRE
EPSS Score
0.2%
Top 93.9%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
No Fix Available
Self-Check
Not available

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

AV:LAC:HPR:LUI:NS:UC:HI:HA:H
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
Open in CVSS calculator →

Weaknesses

CWE-426CWE-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

Click technique nodes for MITRE ATT&CK details · drag to pan · Ctrl/⌘ + scroll to zoom, or go fullscreen.

MITRE ATT&CK

1 technique
Persistence
View detailed technique mapping

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 →
News mentions
Could not load news mentions.

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