CVE-2018-12121: Denial of Service with large HTTP headers

Published Nov 27, 2018
·
Updated

A flaw was found in Node.js versions before 6.15.0, 8.14.0, 10.14.0 and 11.3.0. A Denial of Service with large HTTP headers. By using a combination of many requests with maximum sized headers (almost 80 KB per connection), and carefully timed completion of the headers, it is possible to cause the HTTP server to abort from heap allocation failure. Attack potential is mitigated by the use of a load balancer or other proxy layer.

References: https://nodejs.org/en/blog/vulnerability/november-2018-security-releases/

Other sources

Categorization: Uncontrolled Resource Consumption / Denial of Service (CWE-400)

All versions of 6 and later are vulnerable and the severity is HIGH. By using a combination of many requests with maximum sized headers (almost 80 KB per connection), and carefully timed completion of the headers, it is possible to cause the HTTP server to abort from heap allocation failure. Attack potential is mitigated by the use of a load balancer or other proxy layer.

The total size of HTTP headers received by Node.js now must not exceed 8192 bytes.

Reported by Trevor Norris, fixed by Matteo Collina.

All versions of Node.js 6 (LTS "Boron") are vulnerable

All versions of Node.js 8 (LTS "Carbon") are vulnerable

All versions of Node.js 10 (LTS "Dubnium") are vulnerable

All versions of Node.js 11 (Current) are vulnerable

— Node.Js

CVE-2018-12121 Node.js: All versions prior to Node.js 6.15.0, 8.14.0, 10.14.0 and 11.3.0: Denial of Service with large HTTP headers: By using a combination of many requests with maximum sized headers (almost 80 KB per connection), and carefully timed completion of the headers, it is possible to cause the HTTP server to abort from heap allocation failure. Attack potential is mitigated by the use of a load balancer or other proxy layer. CVE-2018-12122 Node.js: All versions prior to Node.js 6.15.0, 8.14.0, 10.14.0 and 11.3.0: Slowloris HTTP Denial of Service: An attacker can cause a Denial of Service (DoS) by sending headers very slowly keeping HTTP or HTTPS connections and associated resources alive for a long period of time. CVE-2018-12123 Node.js: All versions prior to Node.js 6.15.0, 8.14.0, 10.14.0 and 11.3.0: Hostname spoofing in URL parser for javascript protocol: If a Node.js application is using url.parse() to determine the URL hostname, that hostname can be spoofed by using a mixed case "javascript:" (e.g. "javAscript:") protocol (other protocols are not affected). If security decisions are made about the URL based on the hostname, they may be incorrect.

— F5

Affected Software

66 affected componentsFixes available
Nodejs Node.js>=6.0.0<6.15.0
Nodejs Node.js>=8.0.0<8.14.0
Nodejs Node.js>=10.0.0<10.14.0
Nodejs Node.js>=11.0.0<11.3.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux Desktop=7.0
redhat Enterprise Linux Eus=8.1
redhat Enterprise Linux Eus=8.2
redhat Enterprise Linux Eus=8.4
redhat Enterprise Linux Eus=8.6
redhat Enterprise Linux Server=7.0
redhat Enterprise Linux Server Aus=8.2
redhat Enterprise Linux Server Aus=8.4
redhat Enterprise Linux Server Aus=8.6
redhat Enterprise Linux Server Tus=8.2
redhat Enterprise Linux Server Tus=8.4
redhat Enterprise Linux Server Tus=8.6
redhat Enterprise Linux Workstation=7.0
F5 BIG-IP=17.5.0, >=17.1.0<=17.1.2
17.5.117.1.3
F5 BIG-IP>=16.1.0<=16.1.6
F5 BIG-IP>=15.1.0<=15.1.10
F5 BIG-IP>=14.1.0<=14.1.5
F5 BIG-IP>=13.1.0<=13.1.5
F5 BIG-IQ Centralized Management>=8.0.0<=8.4.0
8.4.1
redhat/nodejs<6.15.0
6.15.0
redhat/nodejs<8.14.0
8.14.0
redhat/nodejs<10.14.0
10.14.0
redhat/nodejs<11.3.0
11.3.0
Node.js Node.js>=6.0.0<6.15.0, >=8.0.0<8.14.0, >=10.0.0<10.14.0, >=11.0.0<11.3.0
6.15.08.14.010.14.011.3.0
Node.js Node.js>=10.0.0<10.14.0
10.14.0
Node.js Node.js>=11.0.0<11.3.0
11.3.0
Node.js Node.js>=6.0.0<6.15.0
6.15.0
Node.js Node.js>=8.0.0<8.14.0
8.14.0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs<8.14.0-r0
8.14.0-r0
alpine/nodejs<10.14.0-r0
10.14.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0
alpine/nodejs-current<11.3.0-r0
11.3.0-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 17.5.117.1.3
  2. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.4.1
  3. Upgrade

    Upgrade redhat/nodejs to a version that resolves this vulnerability.

    Fixed in 6.15.0
  4. Upgrade

    Upgrade redhat/nodejs to a version that resolves this vulnerability.

    Fixed in 8.14.0
  5. Upgrade

    Upgrade redhat/nodejs to a version that resolves this vulnerability.

    Fixed in 10.14.0
  6. Upgrade

    Upgrade redhat/nodejs to a version that resolves this vulnerability.

    Fixed in 11.3.0
  7. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.15.0Fixed in 8.14.0Fixed in 10.14.0Fixed in 11.3.0
  8. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 10.14.0
  9. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 11.3.0
  10. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 6.15.0
  11. Upgrade

    Upgrade to a fixed release to a version that resolves this vulnerability.

    Fixed in 8.14.0
  12. Upgrade

    Upgrade alpine/nodejs to a version that resolves this vulnerability.

    Fixed in 10.14.0-r0
  13. Upgrade

    Upgrade alpine/nodejs to a version that resolves this vulnerability.

    Fixed in 8.14.0-r0
  14. Upgrade

    Upgrade alpine/nodejs-current to a version that resolves this vulnerability.

    Fixed in 11.3.0-r0
  15. Upgrade

    Upgrade Node.js to a version that resolves this vulnerability.

    Fixed in 6.15.0
  16. Upgrade

    Upgrade Node.js to a version that resolves this vulnerability.

    Fixed in 8.14.0
  17. Upgrade

    Upgrade Node.js to a version that resolves this vulnerability.

    Fixed in 10.14.0
  18. Upgrade

    Upgrade Node.js to a version that resolves this vulnerability.

    Fixed in 11.3.0
  19. Compensating control

    Place a load balancer or other proxy layer in front of the Node.js HTTP server to mitigate attack potential.

Event History

Nov 27, 2018
CVE Published
via Node.js·12:00 AM
Data Sourced
via Node.js·12:00 AM
DescriptionSeverityWeaknessAffected Software
Nov 28, 2018
CVE Published
via MITRE·05:00 PM
Data Sourced
via MITRE·05:00 PM
DescriptionWeakness
Data Sourced
via NVD·05:29 PM
RemedyDescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·05:29 PM
DescriptionSeverityAffected Software
Dec 19, 2018
Data Sourced
via Red Hat·07:45 PM
DescriptionSeverityAffected Software
Oct 2, 2023
Advisory Published
via F5·06:55 PM
Data Sourced
via F5·06:55 PM
DescriptionSeverityWeaknessAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2018-12121?

CVE-2018-12121 has been rated as a medium severity vulnerability due to its potential to cause a Denial of Service condition.

2

How do I fix CVE-2018-12121?

To fix CVE-2018-12121, upgrade Node.js to version 6.15.0, 8.14.0, 10.14.0, or 11.3.0 or apply patches provided by your vendor.

3

Which versions of Node.js are affected by CVE-2018-12121?

Node.js versions prior to 6.15.0, 8.14.0, 10.14.0, and 11.3.0 are affected by CVE-2018-12121.

4

What are the potential impacts of CVE-2018-12121?

CVE-2018-12121 could lead to a Denial of Service attack by exploiting large HTTP headers.

5

Is CVE-2018-12121 exploitable remotely?

Yes, CVE-2018-12121 can be exploited remotely through crafted HTTP requests.

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