CVE-2026-107614

An integer underflow in WinCursorShapeUtils::trimTransparent() in GlavSoft TightVNC Server for Windows before 2.8.88 allows a local authenticated user to crash the server, and potentially read out-of-bounds memory, by causing a cursor shape with a width or height of zero to be processed on the DXGI capture path. The loop bound width - 1 wraps to 0xFFFFFFFF, producing an access roughly 4 GB beyond the 64 KB cursor buffer; a monochrome cursor of height 1 also becomes 0 because getCursorHeight() halves the height in place.

CVSS v3 6.1 MEDIUM

6.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 1.8 / Impact : 4.2

Attack Vector LOCAL

Attack Complexity LOW

Privileges Required LOW

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://sourceforge.net/p/vnc-tight/bugs/1661/
https://www.tightvnc.com/whatsnew.php

Configurations

No configuration.

History

08 Oct 2026, 14:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-10-08 14:16

Updated : 2026-10-08 21:10

NVD link : CVE-2026-107614

Mitre link : CVE-2026-107614

CVE.ORG link : CVE-2026-107614

JSON object : View

Products Affected

No product.

CWE

CWE-125

Out-of-bounds Read

CWE-191

Integer Underflow (Wrap or Wraparound)

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