---
title: CVE-2021-3800
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-2021-3800
---

# CVE-2021-3800

Publication date 2 November 2021

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**5.5 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2021-3800#impact-score)

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## Description

A flaw was found in glib before version 2.63.6. Due to random charset
alias, pkexec can leak content from files owned by privileged users to
unprivileged ones under the right condition.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| glib2.0 | 21.10 impish | Not affected |
| 21.04 hirsute | Not affected |
| 20.04 LTS focal | Not affected |
| 18.04 LTS bionic | Fixed 2.56.4-0ubuntu0.18.04.9 |
| 16.04 LTS xenial | Fixed 2.48.2-0ubuntu4.8+esm1  Ubuntu Pro |
| 14.04 LTS trusty | Fixed 2.40.2-0ubuntu1.1+esm4  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)
* [Patch details](https://ubuntu.com/security/CVE-2021-3800#patch-details)

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### 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 |
| --- | --- |
| glib2.0 | * Upstream:   [3529bb4](https://gitlab.gnome.org/GNOME/glib/commit/3529bb4450a51995) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

5.5 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 5.5 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2021-3800)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2021-3800)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2021-3800)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2021-3800)

### Related Ubuntu Security Notices (USN)

+ [USN-5189-1](https://usn.ubuntu.com/USN-5189-1)
+ GLib vulnerability
+ 13 December 2021

### Other references

* <https://access.redhat.com/security/cve/CVE-2021-3800>
* <https://www.openwall.com/lists/oss-security/2017/06/23/8>
* <https://www.cve.org/CVERecord?id=CVE-2021-3800>