CVE-2019-25600

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.

CVSS v3 6.5 MEDIUM

6.5^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.8 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://www.exploit-db.com/exploits/46702
https://www.uvnc.com/
https://www.uvnc.com/downloads/ultravnc/126-download-ultravnc-1224.html
https://www.vulncheck.com/advisories/ultravnc-viewer-denial-of-service-via-buffer-overflow

Configurations

No configuration.

History

No history.

Information

Published : 2026-03-22 14:16

Updated : 2026-03-23 14:31

NVD link : CVE-2019-25600

Mitre link : CVE-2019-25600

CVE.ORG link : CVE-2019-25600

JSON object : View

Products Affected

No product.

CWE

CWE-787

Out-of-bounds Write

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