CVE-2019-25600

UltraVNC Viewer 1.2.2.4 Denial of Service via Buffer Overflow

Published: Mar 22, 2026Updated: Apr 16, 2026 Sources: CVE List NVDCWE-787

6.5MEDIUM

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.

No summary for this CVE yet.

CVSS Vector Breakdown

Exploitability

AV:NAttack Vector

Network

AC:LAttack Complexity

Low

PR:NPrivileges Required

None

UI:RUser Interaction

Required

Scope

S:UScope

Unchanged

Impact

C:NConfidentiality

None

I:NIntegrity

None

A:HAvailability

High

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Weaknesses

CWE-787

Affected Products

Uvnc

commercial

UltraVNC ViewerOn-prem

Consumer Software / file-utility

Exploitability

No known exploits, KEV entries, or remediation guidance available for this vulnerability yet.

Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques

Initial Access

Privilege Escalation

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References

https://www.exploit-db.com/exploits/46702

exploit-db.com

https://www.uvnc.com/

uvnc.com

https://www.uvnc.com/downloads/ultravnc/126-download-ultravnc-1224.html

uvnc.com

and 1 more references View all →

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