CVE-2019-8263

UltraVNC revision 1205 has stack-based buffer overflow vulnerability in VNC client code inside...

6.5 Medium

UltraVNC revision 1205 has stack-based buffer overflow vulnerability in VNC client code inside ShowConnInfo routine, which leads to a denial of service (DoS) condition. This attack appear to be exploitable via network connectivity. User interaction is required to trigger this vulnerability. This vulnerability has been fixed in revision 1206.

Attack profile

How easy it is to exploit

Attack vector: Network
Complexity: Low
Privileges needed: None
User interaction: Required

What an attacker can affect

Confidentiality: None
Integrity: None
Availability: High

Exploit likelihood

2.48%Up 1.2 points since Apr 14, 2021

What each source reports

NVD Score used 6.5

Record: CVE-2019-8263
CVSS 3.1: 6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
CVSS 2.0: 4.3 MediumAV:N/AC:M/Au:N/C:N/I:N/A:P
Weakness: CWE-121, CWE-787
Updated: 2026-11-02

CVE List No score

Record: CVE-2019-8263
Weakness: CWE-121
Updated: 2026-11-02

EUVDEUVD-2019-17661 No score

Record: EUVD-2019-17661
Updated: 2026-11-03

GitHub AdvisoriesGHSA-3ccg-xj7w-w764 6.5

UltraVNC revision 1205 has stack-based buffer overflow vulnerability in VNC client code inside...

Record: GHSA-3ccg-xj7w-w764
CVSS 3.1: 6.5 MediumCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H
Weakness: CWE-787
Updated: 2026-11-02

Affected products

History

History
Recorded	Changed	Sources
Nov 3, 2026	aliases	EUVD
Nov 2, 2026	first indexed	CVE List, GitHub Advisories, NVD

Dates are when Every CVE recorded each change. Upstream dates may differ.

In short

CVE-2019-8263 is a medium vulnerability (CVSS 6.5) in Kaspersky Lab Ultravnc, published March 5, 2019. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 2.48%, the 84th percentile. No source names a fixed version.