---
title: "CVE-2019-9516\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-2019-9516?format=md
keywords: index, follow
---

# CVE-2019-9516

Publication date 13 August 2019

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-2019-9516?format=md#impact-score)

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## Description

Some HTTP/2 implementations are vulnerable to a header leak, potentially
leading to a denial of service. The attacker sends a stream of headers with
a 0-length header name and 0-length header value, optionally Huffman
encoded into 1-byte or greater headers. Some implementations allocate
memory for these headers and keep the allocation alive until the session
dies. This can consume excess memory.

[Read the notes from the security team](https://ubuntu.com/security/CVE-2019-9516?format=md#notes)

## Status

Show unmaintained releases

| Package | Ubuntu Release | Status |
| --- | --- | --- |
| nginx | 19.04 disco | Fixed 1.15.9-0ubuntu1.1 |
| 18.10 cosmic | Ignored end of life, was needed |
| 18.04 LTS bionic | Fixed 1.14.0-0ubuntu1.4 |
| 16.04 LTS xenial | Fixed 1.10.3-0ubuntu0.16.04.4 |
| 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)
* [Patch details](https://ubuntu.com/security/CVE-2019-9516?format=md#patch-details)

## Notes

---

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

nginx added http2 support in 1.9.5

### 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 |
| --- | --- |
| nginx | * Upstream:   [dbdd9ff](https://github.com/nginx/nginx/commit/dbdd9ffea81d9db46fb88b5eba828f2ad080d388) |

## 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-2019-9516)
* [NVD](https://nvd.nist.gov/vuln/detail/CVE-2019-9516)
* [Launchpad](https://launchpad.net/bugs/cve/CVE-2019-9516)
* [Debian](https://security-tracker.debian.org/tracker/CVE-2019-9516)

### Related Ubuntu Security Notices (USN)

+ [USN-4099-1](https://usn.ubuntu.com/USN-4099-1)
+ nginx vulnerabilities
+ 15 August 2019

### Other references

* <https://github.com/Netflix/security-bulletins/blob/master/advisories/third-party/2019-002.md>
* <https://www.cve.org/CVERecord?id=CVE-2019-9516>