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CVE

CWE

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CVE-2019-25600

Published: Mar 22, 2026

Modified: Mar 24, 2026

PUBLISHED

CVSS v3.1

6.5

MEDIUM

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.

Vendor	Product	Versions
Uvnc	UltraVNC Viewer	affected `1.2.2.4`

Weaknesses (CWE)

CVSS v3.1 Details

CVSS v3.1 Vector

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

Attack Vector

Network

Attack Complexity

Low

Privileges Required

None

User Interaction

Required

Scope

Unchanged

Confidentiality

None

Integrity

None

Availability

High

References

ExploitDB-46702

exploit

Official Product Homepage

product

Product Reference

product

VulnCheck Advisory: UltraVNC Viewer 1.2.2.4 Denial of Service via Buffer Overflow

third-party-advisory

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