---
title: "CVE-2021-4010\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-2021-4010?format=md
keywords: index, follow
---

# CVE-2021-4010

Publication date 14 December 2021

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-2021-4010?format=md#impact-score)

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## Description

A flaw was found in xorg-x11-server in versions before 21.1.2 and before
1.20.14. An out-of-bounds access can occur in the SProcScreenSaverSuspend
function. The highest threat from this vulnerability is to data
confidentiality and integrity as well as system availability.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2021-4010?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| xorg-server | 23.04 lunar | Fixed 2:1.20.13-1ubuntu2 |
| 22.10 kinetic | Fixed 2:1.20.13-1ubuntu2 |
| 22.04 LTS jammy | Fixed 2:1.20.13-1ubuntu2 |
| 21.10 impish | Fixed 2:1.20.13-1ubuntu1.1 |
| 21.04 hirsute | Fixed 2:1.20.11-1ubuntu1.2 |
| 20.04 LTS focal | Fixed 2:1.20.13-1ubuntu1~20.04.2 |
| 18.04 LTS bionic | Not affected |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |
| xorg-server-hwe-16.04 | 23.04 lunar | Not in release |
| 22.10 kinetic | Not in release |
| 22.04 LTS jammy | Not in release |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not in release |
| xorg-server-hwe-18.04 | 23.04 lunar | Not in release |
| 22.10 kinetic | Not in release |
| 22.04 LTS jammy | Not in release |
| 21.10 impish | Not in release |
| 21.04 hirsute | Not in release |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Fixed 2:1.20.8-2ubuntu2.2~18.04.6 |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |
| xwayland | 23.04 lunar | Fixed 2:21.1.3-1ubuntu1 |
| 22.10 kinetic | Fixed 2:21.1.3-1ubuntu1 |
| 22.04 LTS jammy | Fixed 2:21.1.3-1ubuntu1 |
| 21.10 impish | Fixed 2:21.1.2-0ubuntu1.1 |
| 21.04 hirsute | Fixed 2:21.1.1-0ubuntu1.1 |
| 20.04 LTS focal | Not in release |
| 18.04 LTS bionic | Not in release |
| 16.04 LTS xenial | Not in release |
| 14.04 LTS trusty | Not in release |

---

* [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)
* [What do statuses mean?](https://ubuntu.com/security/cves/about#statuses)
* [Patch details](https://ubuntu.com/security/CVE-2021-4010?format=md#patch-details)

## Notes

---

### [mdeslaur](https://launchpad.net/~mdeslaur)

xorg server is actually the xorg-server package
the xorg package only contains docs
xwayland package contains parts of xorg-server
This is ZDI-CAN-14951
looks like this was introduced by:
https://gitlab.freedesktop.org/xorg/xserver/-/commit/52048ce29f872192478fece3887b7bc1c8aace7d

### Patch details

For informational purposes only. We recommend not to cherry-pick updates. [How can I get the fixes?](https://ubuntu.com/security/cves/about#security)

| Package | Patch details |
| --- | --- |
| xorg-server | * Upstream:   [6c4c530](https://gitlab.freedesktop.org/xorg/xserver/-/commit/6c4c53010772e3cb4cb8acd54950c8eec9c00d21) |

## 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-2021-4010)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-4010)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2021-4010)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2021-4010)

### Related Ubuntu Security Notices (USN)

+ [USN-5193-1](https://usn.ubuntu.com/USN-5193-1)
+ X.Org X Server vulnerabilities
+ 14 December 2021

### Other references

* <https://www.openwall.com/lists/oss-security/2021/12/14/1>
* <https://www.cve.org/CVERecord?id=CVE-2021-4010>