CVE-2019-25601: uvnc ultravnc launcher Out-of-bounds Write
Vulnerability summary
CVE-2019-25601 is a medium (CVSS 6.9) Out-of-bounds Write vulnerability in uvnc ultravnc launcher. EPSS estimates a 0.27% chance of exploitation in the next 30 days, higher than 17.7% of scored vulnerabilities. 1 public exploit is recorded.
Timeline
- 22-03-2026PublishedVulnerability first disclosed.
- 01-10-2026Last modifiedVulnerability information updated.
Description
UltraVNC Launcher 1.2.2.4 contains a buffer overflow vulnerability in the Path vncviewer.exe property field that allows local attackers to crash the application by supplying an excessively long string. Attackers can input a 300-byte payload of repeated characters through the Properties dialog to trigger a denial of service condition.
CVSS metrics
4 scores · 2 sources · 2 versions- NVDNIST6.9MediumCVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
- NVDNIST6.2MediumCVSS:3.1/AV:L/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS trend
Probability
0.27%
Chance of exploitation in the next 30 days
Percentile
18%
Versus all other CVEs
30-day change
+0.01 pp
From 0.26% on 20-09-2026
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
1 foundUltraVNC Launcher 1.2.2.4 - 'Path' Denial of Service (PoC)
Maturity: poc
Weaknesses
CWE · root causeAffected systems
Uvnc1 product
- ultravnc launcher1.2.2.4
1 vendor · 1 product
References
4 links- www.uvnc.comProduct
- www.vulncheck.com/advisories/ultravnc-launcher-denial-of-service-buffer-overflowThird Party Advisory