CVE-2026-107614
Integer underflow in TightVNC Server cursor shape trimming leads to out-of-bounds read
CVSS Score
6.1
EPSS Score
0.0%
EPSS Percentile
0th
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.
| CWE | CWE-191 CWE-125 |
| Vendor | glavsoft |
| Product | tightvnc |
| Published | Oct 8, 2026 |
| Last Updated | Oct 8, 2026 |
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CVSS v3 Breakdown
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:H Attack Vector
Attack Complexity
Privileges Required
User Interaction
Scope
Confidentiality
Integrity
Availability
Affected Versions
GlavSoft / TightVNC
0 < 2.8.88
References
Credits
Arjun Basnet from Securin