---
title: "CVE-2020-11501\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-2020-11501?format=md
keywords: index, follow
---

# CVE-2020-11501

Publication date 3 April 2020

Last updated 25 August 2025

---

Ubuntu priority

**Medium**

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

## Cvss 3 Severity Score

**7.4 · High**

[Score breakdown](https://ubuntu.com/security/CVE-2020-11501?format=md#impact-score)

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## Description

GnuTLS 3.6.x before 3.6.13 uses incorrect cryptography for DTLS. The
earliest affected version is 3.6.3 (2018-07-16) because of an error in a
2017-10-06 commit. The DTLS client always uses 32 '\0' bytes instead of a
random value, and thus contributes no randomness to a DTLS negotiation.
This breaks the security guarantees of the DTLS protocol.

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| gnutls28 | 19.10 eoan | Fixed 3.6.9-5ubuntu1.1 |
| 18.04 LTS bionic | Not affected |
| 16.04 LTS xenial | Not affected |
| 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-2020-11501?format=md#patch-details)

### 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 |
| --- | --- |
| gnutls28 | * Upstream:   [c01011c](https://gitlab.com/gnutls/gnutls/-/commit/c01011c2d8533dbbbe754e49e256c109cb848d0d) |

## Severity score breakdown

CVSS version:
CVSS v3.0

**Base score**

7.4 · High

* Base metrics

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

  | Parameter | Value |
  | --- | --- |
  | Base score | 7.4 · High |
  | Exploitability score | - |
  | Impact score | - |

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

## References

* [MITRE](https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-11501)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2020-11501)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2020-11501)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2020-11501)

### Related Ubuntu Security Notices (USN)

+ [USN-4322-1](https://usn.ubuntu.com/USN-4322-1)
+ GnuTLS vulnerability
+ 7 April 2020

### Other references

* <https://www.gnutls.org/security-new.html#GNUTLS-SA-2020-03-31>
* <https://gitlab.com/gnutls/gnutls/-/commit/5b595e8e52653f6c5726a4cdd8fddeb6e83804d2>
* <https://www.cve.org/CVERecord?id=CVE-2020-11501>