---
title: "CVE-2020-28019\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-2020-28019?format=md
keywords: index, follow
---

# CVE-2020-28019

Publication date 4 May 2021

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**7.5 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2020-28019?format=md#impact-score)

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## Description

Exim 4 before 4.94.2 has Improper Initialization that can lead to
recursion-based stack consumption or other consequences. This occurs
because use of certain getc functions is mishandled when a client uses BDAT
instead of DATA.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2020-28019?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| exim4 | 22.04 LTS jammy | Fixed 4.94-15ubuntu1.2 |
| 21.10 impish | Fixed 4.94-15ubuntu1.2 |
| 21.04 hirsute | Fixed 4.94-15ubuntu1.2 |
| 20.10 groovy | Fixed 4.94-7ubuntu1.2 |
| 20.04 LTS focal | Fixed 4.93-13ubuntu1.5 |
| 18.04 LTS bionic | Fixed 4.90.1-1ubuntu1.8 |
| 16.04 LTS xenial | Not affected |
| 14.04 LTS trusty | Not affected |

---

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

## Notes

---

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

trusty/xenial ESM not affected.
vulnerability was introduced by: https://git.exim.org/exim.git/patch/7e3ce68e68ab9b8906a637d352993abf361554e2

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.5 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.5 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-28019)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2020-28019)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2020-28019)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2020-28019)

### Related Ubuntu Security Notices (USN)

+ [USN-4934-1](https://usn.ubuntu.com/USN-4934-1)
+ Exim vulnerabilities
+ 4 May 2021

### Other references

* <https://www.cve.org/CVERecord?id=CVE-2020-28019>