# CVE-2020-37132: UltraVNC Launcher 1.2.4.0 - 'Password' Denial of Service

> Local attackers can crash UltraVNC Launcher by pasting an overly long string into the password field, disrupting remote control functionality.

- **Severity:** Medium 6.7 (`CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Not needed
- **Attackable:** Local or same network only
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 5 Feb 2026
- **Updated:** 5 Feb 2026
- **Also known as:** GHSA-755p-gj8q-88j5

## What is CVE-2020-37132?

CVE-2020-37132 is a medium-severity denial of service vulnerability in UltraVNC Launcher, published on 5 Feb 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.

### Official description

UltraVNC Launcher 1.2.4.0 contains a denial of service vulnerability in its password configuration properties that allows local attackers to crash the application. Attackers can paste an overly long 300-character string into the password field to trigger an application crash and prevent normal launcher functionality.

Weakness: CWE-787 (Out-of-bounds Write), CWE-121 (Stack-based Buffer Overflow)

## Which versions are affected by CVE-2020-37132?

It affects 1 product.


Products: Uvnc Ultravnc.

## How do I fix CVE-2020-37132?

No fix has been published for CVE-2020-37132 yet. Limit exposure of the affected software until one is available.

## Is CVE-2020-37132 being exploited?

It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-37132 exists.

## Other vulnerabilities in UltraVNC Launcher

- [CVE-2019-8264](https://insights.sbomify.com/CVE-2019-8264/): Memory corruption in UltraVNC (critical 9.8)
- [CVE-2019-8265](https://insights.sbomify.com/CVE-2019-8265/): Memory corruption in UltraVNC (critical 9.8)
- [CVE-2019-8266](https://insights.sbomify.com/CVE-2019-8266/): Memory corruption in UltraVNC (critical 9.8)
- [CVE-2019-8280](https://insights.sbomify.com/CVE-2019-8280/): Memory corruption in UltraVNC (critical 9.8)
- [CVE-2018-15361](https://insights.sbomify.com/CVE-2018-15361/): Memory corruption in UltraVNC (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2020-37132 and fix it if it is affected.

What it is: CVE-2020-37132 is a medium-severity denial of service vulnerability in UltraVNC Launcher, published on 5 Feb 2026. It can only be exploited from the same machine or local network, and only if a user opens a file or follows a link.
Exploitation: It is not confirmed as exploited in the wild, but public exploit code for CVE-2020-37132 exists.

Affected product: UltraVNC Launcher. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2020-37132/ (Markdown: https://insights.sbomify.com/CVE-2020-37132/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2020-37132
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2020-37132
- OSV: https://osv.dev/vulnerability/CVE-2020-37132

---
From sbomify Insights: https://insights.sbomify.com/CVE-2020-37132/
Summaries are generated and may contain mistakes; the official description above is the record.