Skip to content
OpenAdvisories
High USN-4596-1 4 CVEs

tomcat9 vulnerabilities

Published Oct 21, 2020 · Updated Apr 27, 2026

Ecosystem: Ubuntu

Summary

It was discovered that Tomcat did not properly manage HTTP/2 streams. An
attacker could possibly use this to cause Tomcat to consume resources,
resulting in a denial of service. (CVE-2020-11996)

It was discovered that Tomcat did not properly release the HTTP/1.1
processor after the upgrade to HTTP/2. An attacker could possibly use this
to generate an OutOfMemoryException, resulting in a denial of service.
(CVE-2020-13934)

It was discovered that Tomcat did not properly validate the payload length
in a WebSocket frame. An attacker could possibly use this to trigger an
infinite loop, resulting in a denial of service. (CVE-2020-13935)

It was discovered that Tomcat did not properly deserialize untrusted data.
An attacker could possibly use this issue to execute arbitrary code.
(CVE-2020-9484)

Fixed packages 1

ReleasePackageFixed in
Ubuntu · 20.04 LTS 20.04:LTS tomcat9 9.0.31-1ubuntu0.1

Vulnerabilities 4

  • High 7.5
    CVE-2020-11996 Public exploit EPSS 27%

    Uncontrolled Resource Consumption in Apache Tomcat

    A specially crafted sequence of HTTP/2 requests sent to Apache Tomcat 10.0.0-M1 to 10.0.0-M5, 9.0.0.M1 to 9.0.35 and 8.5.0 to 8.5.55 could trigger high CPU usage for several seconds. If a sufficient number of such requests were made on concurrent HTTP/2 conne…

    Apache Apache Tomcat org.apache.tomcat:tomcat tomcat8 Debian Ubuntu Maven
  • High 7.5
    CVE-2020-13934 EPSS 64%

    Improper Restriction of Operations within the Bounds of a Memory Buffer in Apache Tomcat

    An h2c direct connection to Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M5 to 9.0.36 and 8.5.1 to 8.5.56 did not release the HTTP/1.1 processor after the upgrade to HTTP/2. If a sufficient number of such requests were made, an OutOfMemoryException could occur…

    org.apache.tomcat:tomcat tomcat9 tomcat8 tomcat9 Debian Ubuntu Maven
  • High 7.5
    CVE-2020-13935 Public exploit EPSS 87%

    Infinite Loop in Apache Tomcat

    The payload length in a WebSocket frame was not correctly validated in Apache Tomcat 10.0.0-M1 to 10.0.0-M6, 9.0.0.M1 to 9.0.36, 8.5.0 to 8.5.56 and 7.0.27 to 7.0.104. Invalid payload lengths could trigger an infinite loop. Multiple requests with invalid payl…

    org.apache.tomcat:tomcat tomcat9 tomcat8 tomcat9 Debian Ubuntu Maven
  • High 7.0
    CVE-2020-9484 Public exploit Scanner template EPSS 56%

    Potential remote code execution in Apache Tomcat

    When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to 7.0.103 if a) an attacker is able to control the contents and name of a file on the server; and b) the server is configured to use the PersistenceManage…

    tomcat9 tomcat8 tomcat9 tomcat7 Debian Ubuntu Maven

References

  • report
    https://ubuntu.com/security/CVE-2020-9484
  • report
    https://ubuntu.com/security/CVE-2020-11996
  • report
    https://ubuntu.com/security/CVE-2020-13934
  • report
    https://ubuntu.com/security/CVE-2020-13935