USN-4596-1: Tomcat vulnerabilities

Releases

• Ubuntu 20.04 LTS

Packages

• tomcat9 - Apache Tomcat 9 - Servlet and JSP engine

Details

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)

Update instructions

The problem can be corrected by updating your system to the following package versions:

Ubuntu 20.04

• libtomcat9-embed-java - 9.0.31-1ubuntu0.1
• libtomcat9-java - 9.0.31-1ubuntu0.1
• tomcat9 - 9.0.31-1ubuntu0.1
• tomcat9-common - 9.0.31-1ubuntu0.1

In general, a standard system update will make all the necessary changes.

References

• CVE-2020-9484
• CVE-2020-13934
• CVE-2020-11996
• CVE-2020-13935

Related notices

• USN-4448-1
• USN-5360-1
• USN-6908-1
• USN-6943-1