---
title: "CVE-2020-8622\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-2020-8622?format=md
keywords: index, follow
---

# CVE-2020-8622

Publication date 20 August 2020

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**6.5 · Medium**

[Score breakdown](https://ubuntu.com/security/CVE-2020-8622?format=md#impact-score)

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## Description

In BIND 9.0.0 -> 9.11.21, 9.12.0 -> 9.16.5, 9.17.0 -> 9.17.3, also affects
9.9.3-S1 -> 9.11.21-S1 of the BIND 9 Supported Preview Edition, An attacker
on the network path for a TSIG-signed request, or operating the server
receiving the TSIG-signed request, could send a truncated response to that
request, triggering an assertion failure, causing the server to exit.
Alternately, an off-path attacker would have to correctly guess when a
TSIG-signed request was sent, along with other characteristics of the
packet and message, and spoof a truncated response to trigger an assertion
failure, causing the server to exit.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2020-8622?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| bind9 | 20.04 LTS focal | Fixed 1:9.16.1-0ubuntu2.3 |
| 18.04 LTS bionic | Fixed 1:9.11.3+dfsg-1ubuntu1.13 |
| 16.04 LTS xenial | Fixed 1:9.10.3.dfsg.P4-8ubuntu1.17 |
| 14.04 LTS trusty | Fixed 1:9.9.5.dfsg-3ubuntu0.19+esm3  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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## Notes

---

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

Affects versions 9.0.0 -> 9.11.21, 9.12.0 -> 9.16.5, 9.17.0 -> 9.17.3, also affects 9.9.3-S1 -> 9.11.21-S1 of the BIND Supported Preview Edition

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

6.5 · Medium

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 6.5 · Medium |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-8622)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2020-8622)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2020-8622)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2020-8622)

### Related Ubuntu Security Notices (USN)

+ [USN-4468-1](https://usn.ubuntu.com/USN-4468-1)
+ Bind vulnerabilities
+ 21 August 2020

+ [USN-4468-2](https://usn.ubuntu.com/USN-4468-2)
+ Bind vulnerability
+ 24 August 2020

### Other references

* <https://kb.isc.org/docs/cve-2020-8622>
* <https://www.cve.org/CVERecord?id=CVE-2020-8622>