---
title: "CVE-2020-4044\n    | Ubuntu"
description: Ubuntu is an open source software operating system that runs from the
  desktop, to the cloud, to all your internet connected things.
url: https://ubuntu.com/security/CVE-2020-4044?format=md
keywords: index, follow
---

# CVE-2020-4044

Publication date 30 June 2020

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

[Why this priority?](https://ubuntu.com/security/cves/about#priority )

## Cvss 3 Severity Score

**7.8 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2020-4044?format=md#impact-score)

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## Description

The xrdp-sesman service before version 0.9.13.1 can be crashed by
connecting over port 3350 and supplying a malicious payload. Once the
xrdp-sesman process is dead, an unprivileged attacker on the server could
then proceed to start their own imposter sesman service listening on port
3350. This will allow them to capture any user credentials that are
submitted to XRDP and approve or reject arbitrary login credentials. For
xorgxrdp sessions in particular, this allows an unauthorized user to hijack
an existing session. This is a buffer overflow attack, so there may be a
risk of arbitrary code execution as well.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| xrdp | 23.10 mantic | Not affected |
| 23.04 lunar | Not affected |
| 22.10 kinetic | Not affected |
| 22.04 LTS jammy | Not affected |
| 21.10 impish | Not affected |
| 21.04 hirsute | Not affected |
| 20.10 groovy | Not affected |
| 20.04 LTS focal | Fixed 0.9.12-1ubuntu0.1 |
| 19.10 eoan | Ignored end of life |
| 18.04 LTS bionic | Fixed 0.9.5-2ubuntu0.1~esm1  Ubuntu Pro |
| 16.04 LTS xenial | Fixed 0.6.1-2ubuntu0.3+esm2  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 0.6.0-1ubuntu0.1+esm2  Ubuntu Pro |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)

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## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.8 · High

* Base metrics

  | Parameter | Value |
  | --- | --- |
  | Attack vector | Local |
  | Attack complexity | Low |
  | Privileges required | Low |
  | User interaction | None |
  | Scope | Unchanged |
  | Confidentiality impact | High |
  | Integrity impact | High |
  | Availability impact | High |
* Scores

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.8 · High |
  | Exploitability score | - |
  | Impact score | - |

**Vector:** CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-4044)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2020-4044)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2020-4044)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2020-4044)

### Related Ubuntu Security Notices (USN)

+ [USN-6469-1](https://usn.ubuntu.com/USN-6469-1)
+ xrdp vulnerability
+ 2 November 2023

### Other references

* <https://github.com/neutrinolabs/xrdp/commit/0c791d073d0eb344ee7aaafd221513dc9226762c>
* <https://github.com/neutrinolabs/xrdp/releases/tag/v0.9.13.1>
* <https://github.com/neutrinolabs/xrdp/security/advisories/GHSA-j9fv-6fwf-p3g4>
* <https://www.cve.org/CVERecord?id=CVE-2020-4044>