high
7.5
CWE
401 476 400
Advisory Published
Updated

CVE-2020-13934: Null Pointer Dereference

First published: Tue Jul 14 2020(Updated: )

A flaw was found in Apache Tomcat, where an h2c direct connection did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests are made, an OutOfMemoryException could occur, leading to a denial of service. The highest threat from this vulnerability is to system availability.

Credit: security@apache.org

Affected SoftwareAffected VersionHow to fix
redhat/jws5-tomcat<0:9.0.30-5.redhat_6.1.el6
0:9.0.30-5.redhat_6.1.el6
redhat/jws5-tomcat<0:9.0.30-5.redhat_6.1.el7
0:9.0.30-5.redhat_6.1.el7
redhat/jws5-tomcat<0:9.0.30-5.redhat_6.1.el8
0:9.0.30-5.redhat_6.1.el8
redhat/tomcat<10.0.0
10.0.0
redhat/tomcat<9.0.37
9.0.37
redhat/tomcat<8.5.57
8.5.57
IBM IBM® Engineering Requirements Management DOORS<=9.7.2.7
IBM IBM® Engineering Requirements Management DOORS Web Access<=9.7.2.7
debian/tomcat9
9.0.43-2~deb11u10
9.0.43-2~deb11u11
9.0.70-2
9.0.95-1
Apache Tomcat>=8.5.1<=8.5.56
Apache Tomcat>=9.0.1<=9.0.36
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-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-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
Apache Tomcat=10.0.0-milestone1
Apache Tomcat=10.0.0-milestone2
Apache Tomcat=10.0.0-milestone3
Apache Tomcat=10.0.0-milestone4
Apache Tomcat=10.0.0-milestone5
Apache Tomcat=10.0.0-milestone6
Debian GNU/Linux=9.0
Debian GNU/Linux=10.0
NetApp OnCommand System Manager>=3.0.0<=3.1.3
openSUSE=15.1
openSUSE=15.2
Ubuntu Linux=20.04
Oracle Agile Engineering Data Management=6.2.1.0
Oracle Agile PLM=9.3.3
Oracle Agile PLM=9.3.5
Oracle Agile PLM=9.3.6
Oracle Communications Instant Messaging Server=10.0.1.5.0
Oracle Fusion Middleware Platform=12.2.1.3.0
Oracle Fusion Middleware Platform=12.2.1.4.0
oracle instantis enterprisetrack=17.1
oracle instantis enterprisetrack=17.2
oracle instantis enterprisetrack=17.3
Oracle Managed File Transfer=12.2.1.3.0
Oracle Managed File Transfer=12.2.1.4.0
MySQL Enterprise Monitor<=8.0.21
Oracle Siebel User Interface Framework<=20.12
Oracle Workload Manager=12.2.0.1
Oracle Workload Manager=18c
Oracle Workload Manager=19c
Debian=9.0
Debian=10.0
Ubuntu=20.04

Remedy

https://www.oracle.com//security-alerts/cpujul2021.html

Remedy

https://www.oracle.com/security-alerts/cpuApr2021.html

Remedy

https://www.oracle.com/security-alerts/cpujan2021.html

Remedy

https://www.oracle.com/security-alerts/cpujan2022.html

Remedy

https://www.oracle.com/security-alerts/cpuoct2020.html

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2020-13934?

    CVE-2020-13934 has been classified as a medium severity vulnerability due to the potential for denial of service from an OutOfMemoryException.

  • How do I fix CVE-2020-13934?

    To mitigate CVE-2020-13934, upgrade to one of the fixed versions such as Apache Tomcat 8.5.57, 9.0.37, or 10.0.0.

  • Which versions of Apache Tomcat are affected by CVE-2020-13934?

    CVE-2020-13934 affects Apache Tomcat versions from 8.5.1 to 8.5.56, and from 9.0.1 to 9.0.36.

  • What causes the vulnerability CVE-2020-13934?

    CVE-2020-13934 is caused by an h2c direct connection not releasing the HTTP/1.1 processor after the upgrade to HTTP/2.

  • What impacts can CVE-2020-13934 have on my server?

    If exploited, CVE-2020-13934 can lead to an OutOfMemoryException, resulting in a denial of service on the affected server.

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