CVE-2020-37132
BaseFortify
Publication date: 2026-02-05
Last updated on: 2026-02-09
Assigner: VulnCheck
Description
Description
CVSS Scores
EPSS Scores
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Meta Information
Affected Vendors & Products
| Vendor | Product | Version / Range |
|---|---|---|
| uvnc | ultravnc | to 1.2.4.0 (inc) |
Helpful Resources
Exploitability
| CWE ID | Description |
|---|---|
| CWE-121 | A stack-based buffer overflow condition is a condition where the buffer being overwritten is allocated on the stack (i.e., is a local variable or, rarely, a parameter to a function). |
| CWE-787 | The product writes data past the end, or before the beginning, of the intended buffer. |
Attack-Flow Graph
AI Powered Q&A
Can you explain this vulnerability to me?
CVE-2020-37132 is a denial of service vulnerability in UltraVNC Launcher version 1.2.4.0. It occurs in the password configuration properties where an attacker can paste an overly long string of 300 characters into the password field. This triggers a stack-based buffer overflow that causes the application to crash, disrupting normal launcher functionality.
How can this vulnerability impact me? :
This vulnerability allows a local attacker to crash the UltraVNC Launcher application by exploiting the password field with a specially crafted long string. The impact is a denial of service, meaning the launcher becomes unusable until restarted or fixed, preventing normal remote desktop session setup through the launcher.
How does this vulnerability affect compliance with common standards and regulations (like GDPR, HIPAA)?:
I don't know
How can this vulnerability be detected on my network or system? Can you suggest some commands?
[{'type': 'paragraph', 'content': 'This vulnerability is a local denial of service issue triggered by pasting an overly long 300-character string into the UltraVNC Launcher password field, causing the application to crash.'}, {'type': 'paragraph', 'content': 'Detection involves verifying if the UltraVNC Launcher version 1.2.4.0 is installed and testing the password field by pasting a 300-character string to see if the application crashes.'}, {'type': 'paragraph', 'content': "A proof-of-concept method includes creating a text file containing 300 'A' characters, copying it to the clipboard, and pasting it into the password field in the UltraVNC Launcher properties to observe if the application crashes."}, {'type': 'paragraph', 'content': 'No specific network commands or automated detection tools are provided in the available information.'}] [2, 3]
What immediate steps should I take to mitigate this vulnerability?
To mitigate this vulnerability, avoid pasting or entering excessively long strings (300 characters or more) into the UltraVNC Launcher password field.
Restrict local user access to the UltraVNC Launcher application to prevent untrusted users from triggering the denial of service.
Monitor for updates or patches from the UltraVNC project and apply them once available to address this vulnerability.
As this is a local vulnerability requiring user interaction, enforcing strict user permissions and educating users about this issue can help reduce risk.