CVE-2020-1935: XSS

Published Feb 24, 2020
·
Updated

A flaw was found in Apache Tomcat. The HTTP header parsing code used an approach to end-of-line (EOL) parsing that allowed some invalid HTTP headers to be parsed as valid. This led to the possibility of HTTP Request Smuggling if Tomcat was located behind a reverse proxy that incorrectly handled the invalid Transfer-Encoding header in a particular manner. The highest threat with this vulnerability is system availability.

Other sources

Apache Tomcat is vulnerable to HTTP request smuggling, caused by a flaw when handling unusual Transfer-Encoding HTTP header. By sending a specially-crafted request, an attacker could exploit this vulnerability to poison the web cache, bypass web application firewall protection, and conduct XSS attacks.

— IBM

In Apache Tomcat 9.0.0.M1 to 9.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99 the HTTP header parsing code used an approach to end-of-line parsing that allowed some invalid HTTP headers to be parsed as valid. This led to a possibility of HTTP Request Smuggling if Tomcat was located behind a reverse proxy that incorrectly handled the invalid Transfer-Encoding header in a particular manner. Such a reverse proxy is considered unlikely.

The HTTP header parsing code used an approach to end-of-line (EOL) parsing that allowed some invalid HTTP headers to be parsed as valid. This led to a possibility of HTTP Request Smuggling if Tomcat was located behind a reverse proxy that incorrectly handled the invalid Transfer-Encoding header in a particular manner. Such a reverse proxy is considered unlikely.

It affects the version of Apache Tomcat 9 from 9.0.0.M1 to 9.0.30, Tomcat from 8 8.5.0 to 8.5.50, and Tomcat 7 7.0.0 to 7.0.99.

Upstream Patches: https://github.com/apache/tomcat/commit/8bfb0ff / tomcat9 https://github.com/apache/tomcat/commit/8fbe2e9 / tomcat8 https://github.com/apache/tomcat/commit/702bf15 / tomcat7

— Red Hat

Affected Software

78 affected componentsFixes available
redhat/tomcat<0:7.0.76-16.el7_9
0:7.0.76-16.el7_9
redhat/tomcat<0:7.0.76-11.el7_6
0:7.0.76-11.el7_6
redhat/tomcat<0:7.0.76-12.el7_7
0:7.0.76-12.el7_7
redhat/tomcat7<0:7.0.70-41.ep7.el6
0:7.0.70-41.ep7.el6
redhat/tomcat8<0:8.0.36-45.ep7.el6
0:8.0.36-45.ep7.el6
redhat/tomcat7<0:7.0.70-41.ep7.el7
0:7.0.70-41.ep7.el7
redhat/tomcat8<0:8.0.36-45.ep7.el7
0:8.0.36-45.ep7.el7
redhat/jws5-tomcat<0:9.0.30-3.redhat_4.1.el6
0:9.0.30-3.redhat_4.1.el6
redhat/jws5-tomcat-native<0:1.2.23-4.redhat_4.el6
0:1.2.23-4.redhat_4.el6
redhat/jws5-tomcat<0:9.0.30-3.redhat_4.1.el7
0:9.0.30-3.redhat_4.1.el7
redhat/jws5-tomcat-native<0:1.2.23-4.redhat_4.el7
0:1.2.23-4.redhat_4.el7
redhat/jws5-tomcat<0:9.0.30-3.redhat_4.1.el8
0:9.0.30-3.redhat_4.1.el8
redhat/jws5-tomcat-native<0:1.2.23-4.redhat_4.el8
0:1.2.23-4.redhat_4.el8
redhat/tomcat<9.0.31
9.0.31
redhat/tomcat<8.5.51
8.5.51
redhat/tomcat<7.0.100
7.0.100
IBM Data Risk Manager<=2.0.6
Apache Tomcat>=7.0.0<=7.0.99
Apache Tomcat>=8.5.0<=8.5.50
Apache Tomcat>=9.0.0<=9.0.30
Apache Tomcat=9.0.0
Apache Tomcat=9.0.0-milestone1
Apache Tomcat=9.0.0-milestone10
Apache Tomcat=9.0.0-milestone11
Apache Tomcat=9.0.0-milestone12
Apache Tomcat=9.0.0-milestone13
Apache Tomcat=9.0.0-milestone14
Apache Tomcat=9.0.0-milestone15
Apache Tomcat=9.0.0-milestone16
Apache Tomcat=9.0.0-milestone17
Apache Tomcat=9.0.0-milestone18
Apache Tomcat=9.0.0-milestone19
Apache Tomcat=9.0.0-milestone2
Apache Tomcat=9.0.0-milestone20
Apache Tomcat=9.0.0-milestone21
Apache Tomcat=9.0.0-milestone22
Apache Tomcat=9.0.0-milestone23
Apache Tomcat=9.0.0-milestone24
Apache Tomcat=9.0.0-milestone25
Apache Tomcat=9.0.0-milestone26
Apache Tomcat=9.0.0-milestone27
Apache Tomcat=9.0.0-milestone3
Apache Tomcat=9.0.0-milestone4
Apache Tomcat=9.0.0-milestone5
Apache Tomcat=9.0.0-milestone6
Apache Tomcat=9.0.0-milestone7
Apache Tomcat=9.0.0-milestone8
Apache Tomcat=9.0.0-milestone9
Debian Debian Linux=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
Canonical Ubuntu Linux=16.04
openSUSE Leap=15.1
NetApp Data Availability Services
NetApp OnCommand System Manager>=3.0.0<=3.1.3
Oracle Agile Engineering Data Management=6.2.1.0
Oracle Agile Product Lifecycle Management=9.3.3
Oracle Agile Product Lifecycle Management=9.3.5
Oracle Agile Product Lifecycle Management=9.3.6
Oracle Communications Element Manager=8.1.1
Oracle Communications Element Manager=8.2.0
Oracle Communications Element Manager=8.2.1
Oracle Communications Instant Messaging Server=10.0.1.4.0
Oracle Health Sciences Empirica Inspections=1.0.1.2
Oracle Health Sciences Empirica Signal=7.3.3
Oracle Hospitality Guest Access=4.2.0
Oracle Hospitality Guest Access=4.2.1
Oracle Hyperion Infrastructure Technology=11.1.2.4
Oracle Instantis Enterprisetrack>=17.1<=17.3
Oracle MySQL Enterprise Monitor>=4.0.0<=4.0.12
Oracle MySQL Enterprise Monitor>=8.0.0<=8.0.20
Oracle Retail Order Broker=15.0
Oracle Siebel UI Framework<=20.5
Oracle Transportation Management=6.3.7
Oracle Workload Manager=12.2.0.1
Oracle Workload Manager=18c
Oracle Workload Manager=19c
debian/tomcat9
9.0.43-2~deb11u109.0.43-2~deb11u129.0.70-29.0.95-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 0:7.0.76-16.el7_9
  2. Upgrade

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

    Fixed in 0:7.0.76-11.el7_6
  3. Upgrade

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

    Fixed in 0:7.0.76-12.el7_7
  4. Upgrade

    Upgrade redhat/tomcat7 to a version that resolves this vulnerability.

    Fixed in 0:7.0.70-41.ep7.el6
  5. Upgrade

    Upgrade redhat/tomcat8 to a version that resolves this vulnerability.

    Fixed in 0:8.0.36-45.ep7.el6
  6. Upgrade

    Upgrade redhat/tomcat7 to a version that resolves this vulnerability.

    Fixed in 0:7.0.70-41.ep7.el7
  7. Upgrade

    Upgrade redhat/tomcat8 to a version that resolves this vulnerability.

    Fixed in 0:8.0.36-45.ep7.el7
  8. Upgrade

    Upgrade redhat/jws5-tomcat to a version that resolves this vulnerability.

    Fixed in 0:9.0.30-3.redhat_4.1.el6
  9. Upgrade

    Upgrade redhat/jws5-tomcat-native to a version that resolves this vulnerability.

    Fixed in 0:1.2.23-4.redhat_4.el6
  10. Upgrade

    Upgrade redhat/jws5-tomcat to a version that resolves this vulnerability.

    Fixed in 0:9.0.30-3.redhat_4.1.el7
  11. Upgrade

    Upgrade redhat/jws5-tomcat-native to a version that resolves this vulnerability.

    Fixed in 0:1.2.23-4.redhat_4.el7
  12. Upgrade

    Upgrade redhat/jws5-tomcat to a version that resolves this vulnerability.

    Fixed in 0:9.0.30-3.redhat_4.1.el8
  13. Upgrade

    Upgrade redhat/jws5-tomcat-native to a version that resolves this vulnerability.

    Fixed in 0:1.2.23-4.redhat_4.el8
  14. Upgrade

    Upgrade debian/tomcat9 to a version that resolves this vulnerability.

    Fixed in 9.0.43-2~deb11u10Fixed in 9.0.43-2~deb11u12Fixed in 9.0.70-2Fixed in 9.0.95-1
  15. Upgrade

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

    Fixed in 9.0.31
  16. Upgrade

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

    Fixed in 8.5.51
  17. Upgrade

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

    Fixed in 7.0.100
  18. Upgrade

    Upgrade tomcat7 to a version that resolves this vulnerability.

    Fixed in 7.0.99
  19. Upgrade

    Upgrade tomcat8 to a version that resolves this vulnerability.

    Fixed in 8.5.50
  20. Upgrade

    Upgrade tomcat9 to a version that resolves this vulnerability.

    Fixed in 9.0.30
  21. Compensating control

    For Red Hat Satellite 6: add an iptables rule to deny TCP requests of Tomcat that are not originating from the Satellite.

Event History

Feb 24, 2020
CVE Published
12:00 AM
CVE Published
via MITRE·09:11 PM
Data Sourced
via MITRE·09:11 PM
DescriptionWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
Feb 25, 2020
Data Sourced
via Red Hat·06:33 AM
DescriptionSeverityAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:44 PM
Description
Sep 16, 2024
Data Sourced
via Ubuntu·02:24 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2020-1935?

CVE-2020-1935 has a moderate severity level due to the potential for HTTP request smuggling.

2

How do I fix CVE-2020-1935?

To fix CVE-2020-1935, upgrade to Apache Tomcat version 7.0.100, 8.5.51, or 9.0.31 or later.

3

Which versions of Apache Tomcat are affected by CVE-2020-1935?

CVE-2020-1935 affects Apache Tomcat versions before 7.0.100, 8.5.51, and 9.0.31.

4

What is HTTP request smuggling related to CVE-2020-1935?

HTTP request smuggling involves sending maliciously crafted requests that can bypass security controls by exploiting the flawed header parsing.

5

Is CVE-2020-1935 applicable to reverse proxy configurations?

Yes, CVE-2020-1935 is particularly concerning when Tomcat is deployed behind a reverse proxy that does not handle headers correctly.

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