CVE-2019-25600 (GCVE-0-2019-25600)
Vulnerability from cvelistv5 – Published: 2026-03-22 13:38 – Updated: 2026-03-24 15:14
VLAI
EPSS
VEX
Title
UltraVNC Viewer 1.2.2.4 Denial of Service via Buffer Overflow
Summary
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.
Severity
SSVC
Exploitation: poc
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-03-24 14:09 UTC
CWE
- CWE-787 - Out-of-bounds Write
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://www.exploit-db.com/exploits/46702 | exploit |
| https://www.uvnc.com/ | product |
| https://www.uvnc.com/downloads/ultravnc/126-downl… | product |
| https://www.vulncheck.com/advisories/ultravnc-vie… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Uvnc | UltraVNC Viewer |
Affected:
1.2.2.4
|
guessed |
Date Public
2019-04-14 00:00
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