CVE-2019-25600

MEDIUM

6.5

Description

UltraVNC Viewer 1.2.2.4 contains a denial of service vulnerability that allows attackers to crash the application by supplying an oversized string to the VNC Server input field. Attackers can paste a malicious string containing 256 repeated characters into the VNC Server field and click Connect to trigger a buffer overflow that crashes the viewer.

CVE Details

CVSS v3.1 Score6.5

SeverityMEDIUM

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:N/I:N/A:H

Attack VectorNETWORK

ComplexityLOW

Privileges RequiredNONE

User InteractionREQUIRED

Published3/22/2026

Last Modified3/23/2026

Sourcenvd

Honeypot Sightings0

Weaknesses (CWE)

CWE-787

References

https://www.exploit-db.com/exploits/46702(disclosure@vulncheck.com)

https://www.uvnc.com/(disclosure@vulncheck.com)

https://www.uvnc.com/downloads/ultravnc/126-download-ultravnc-1224.html(disclosure@vulncheck.com)

https://www.vulncheck.com/advisories/ultravnc-viewer-denial-of-service-via-buffer-overflow(disclosure@vulncheck.com)

IOC Correlations

No correlations recorded

This product uses data from the NVD API but is not endorsed or certified by the NVD.