medium
5.3
CWE
200
Advisory Published
CVE Published
Advisory Published
Updated

CVE-2020-13943: Infoleak

First published: Mon Oct 12 2020(Updated: )

A flaw was found in Apache Tomcat. If an HTTP/2 client exceeded the agreed maximum number of concurrent streams for a connection (in violation of the HTTP/2 protocol), it is possible that a subsequent request made on that connection could contain HTTP headers - including HTTP/2 pseudo headers - from a previous request rather than the intended headers. This could lead to users seeing responses for unexpected resources. The highest threat from this vulnerability is to data confidentiality.

Credit: security@apache.org

Affected SoftwareAffected VersionHow to fix
maven/org.apache.tomcat:tomcat-coyote>=8.5.0<=8.5.57
8.5.58
maven/org.apache.tomcat:tomcat-coyote>=9.0.0-M1<=9.0.37
9.0.38
maven/org.apache.tomcat:tomcat-coyote>=10.0.0-M1<=10.0.0-M7
10.0.0-M8
redhat/jws5-tomcat<0:9.0.36-9.redhat_8.1.el7
0:9.0.36-9.redhat_8.1.el7
redhat/jws5-tomcat-native<0:1.2.25-3.redhat_3.el7
0:1.2.25-3.redhat_3.el7
redhat/jws5-tomcat<0:9.0.36-9.redhat_8.1.el8
0:9.0.36-9.redhat_8.1.el8
redhat/jws5-tomcat-native<0:1.2.25-3.redhat_3.el8
0:1.2.25-3.redhat_3.el8
redhat/tomcat<10.0.0
10.0.0
redhat/tomcat<9.0.38
9.0.38
redhat/tomcat<8.5.58
8.5.58
debian/tomcat9
9.0.43-2~deb11u10
9.0.43-2~deb11u11
9.0.70-2
9.0.95-1
IBM Engineering Requirements Management DOORS Web Access<=9.7.2.7
IBM Rational DOORS Web Access<=9.7.2.7
Tomcat=8.5.0
Tomcat=8.5.1
Tomcat=8.5.2
Tomcat=8.5.3
Tomcat=8.5.4
Tomcat=8.5.5
Tomcat=8.5.6
Tomcat=8.5.7
Tomcat=8.5.8
Tomcat=8.5.9
Tomcat=8.5.10
Tomcat=8.5.11
Tomcat=8.5.12
Tomcat=8.5.13
Tomcat=8.5.14
Tomcat=8.5.15
Tomcat=8.5.16
Tomcat=8.5.17
Tomcat=8.5.18
Tomcat=8.5.19
Tomcat=8.5.20
Tomcat=8.5.21
Tomcat=8.5.22
Tomcat=8.5.23
Tomcat=8.5.24
Tomcat=8.5.25
Tomcat=8.5.26
Tomcat=8.5.27
Tomcat=8.5.28
Tomcat=8.5.29
Tomcat=8.5.30
Tomcat=8.5.31
Tomcat=8.5.32
Tomcat=8.5.33
Tomcat=8.5.34
Tomcat=8.5.35
Tomcat=8.5.36
Tomcat=8.5.37
Tomcat=8.5.38
Tomcat=8.5.39
Tomcat=8.5.40
Tomcat=8.5.41
Tomcat=8.5.42
Tomcat=8.5.43
Tomcat=8.5.44
Tomcat=8.5.45
Tomcat=8.5.46
Tomcat=8.5.47
Tomcat=8.5.48
Tomcat=8.5.49
Tomcat=8.5.50
Tomcat=8.5.51
Tomcat=8.5.52
Tomcat=8.5.53
Tomcat=8.5.54
Tomcat=8.5.55
Tomcat=8.5.56
Tomcat=8.5.57
Tomcat=9.0.0-milestone10
Tomcat=9.0.0-milestone11
Tomcat=9.0.0-milestone12
Tomcat=9.0.0-milestone13
Tomcat=9.0.0-milestone14
Tomcat=9.0.0-milestone15
Tomcat=9.0.0-milestone16
Tomcat=9.0.0-milestone17
Tomcat=9.0.0-milestone18
Tomcat=9.0.0-milestone19
Tomcat=9.0.0-milestone20
Tomcat=9.0.0-milestone21
Tomcat=9.0.0-milestone22
Tomcat=9.0.0-milestone23
Tomcat=9.0.0-milestone24
Tomcat=9.0.0-milestone25
Tomcat=9.0.0-milestone26
Tomcat=9.0.0-milestone27
Tomcat=9.0.0-milestone5
Tomcat=9.0.0-milestone6
Tomcat=9.0.0-milestone7
Tomcat=9.0.0-milestone8
Tomcat=9.0.0-milestone9
Tomcat=9.0.1
Tomcat=9.0.2
Tomcat=9.0.3
Tomcat=9.0.4
Tomcat=9.0.5
Tomcat=9.0.6
Tomcat=9.0.7
Tomcat=9.0.8
Tomcat=9.0.9
Tomcat=9.0.10
Tomcat=9.0.11
Tomcat=9.0.12
Tomcat=9.0.13
Tomcat=9.0.14
Tomcat=9.0.15
Tomcat=9.0.16
Tomcat=9.0.17
Tomcat=9.0.18
Tomcat=9.0.19
Tomcat=9.0.20
Tomcat=9.0.21
Tomcat=9.0.22
Tomcat=9.0.23
Tomcat=9.0.24
Tomcat=9.0.25
Tomcat=9.0.26
Tomcat=9.0.27
Tomcat=9.0.28
Tomcat=9.0.29
Tomcat=9.0.30
Tomcat=9.0.31
Tomcat=9.0.32
Tomcat=9.0.33
Tomcat=9.0.34
Tomcat=9.0.35
Tomcat=9.0.36
Tomcat=9.0.37
Tomcat=10.0.0-milestone1
Tomcat=10.0.0-milestone2
Tomcat=10.0.0-milestone3
Tomcat=10.0.0-milestone4
Tomcat=10.0.0-milestone5
Tomcat=10.0.0-milestone6
Tomcat=10.0.0-milestone7
Debian=9.0
Debian=10.0
Oracle Instantis EnterpriseTrack=17.1
Oracle Instantis EnterpriseTrack=17.2
Oracle Instantis EnterpriseTrack=17.3
Oracle SD-WAN Edge=9.0

Remedy

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

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2020-13943?

    CVE-2020-13943 has been rated as a medium severity vulnerability.

  • How do I fix CVE-2020-13943?

    To mitigate CVE-2020-13943, upgrade to Apache Tomcat version 8.5.58, 9.0.38, or 10.0.0-M8.

  • Which versions of Apache Tomcat are affected by CVE-2020-13943?

    CVE-2020-13943 affects Apache Tomcat versions from 8.5.0 to 8.5.57, and from 9.0.0-M1 to 9.0.37.

  • What is the main issue described in CVE-2020-13943?

    CVE-2020-13943 involves an issue where HTTP/2 clients can exceed the maximum number of concurrent streams leading to header leakage.

  • Which products are impacted by CVE-2020-13943?

    CVE-2020-13943 impacts Apache Tomcat as well as IBM® Engineering Requirements Management DOORS and its Web Access version.

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