Vulnerability · Published Feb 5, 2026 · Assigned by VulnCheck
CVE-2020-37133UltraVNC Launcher 1.2.4.0 - 'RepeaterHost' Denial of Service
High 7.5
In plain English
A high-severity stack buffer overflow in UltraVNC Launcher from UltraVNC Team. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.5% (higher than 45% of all known vulnerabilities).
Severity (CVSS 3.1)7.5High
Exploit odds (30 days)0.5%top 54.5% of all CVEs
Exploited in the wildNo reportsCISA SSVC: poc
Attack toolingNoneno public tooling known
Official description
UltraVNC Launcher 1.2.4.0 contains a denial of service vulnerability in the Repeater Host configuration field that allows attackers to crash the application. Attackers can paste an overly long string of 300 characters into the Repeater Host property to trigger an application crash.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| UltraVNC Team | UltraVNC Launcher | 1.2.4.0 |
Weakness: CWE-121 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
References
- ExploitDB-48288 exploit
- UltraVNC Official Homepage product
- VulnCheck Advisory: UltraVNC Launcher 1.2.4.0 - 'RepeaterHost' Denial of Service third-party-advisory