PT-2026-26988 · Uvnc · Ultravnc Viewer

Victor Mondragón · Published 2026-03-22 · Updated 2026-03-22 · CVE-2019-25600

NVD

CVSS v3.1

6.5

Medium

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

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.

Exploit

Fix

Memory Corruption

Weakness Enumeration

CWE-787

Related Identifiers

CVE-2019-25600

Affected Products

Ultravnc Viewer

References · 5

• 🔥 https://exploit-db.com/exploits/46702 · Exploit
• https://nvd.nist.gov/vuln/detail/CVE-2019-25600 · Security Note
• https://vulncheck.com/advisories/ultravnc-viewer-denial-of-service-via-buffer-overflow · Note
• https://uvnc.com/downloads/ultravnc/126-download-ultravnc-1224.html · Note
• https://uvnc.com · Note