==========================================================================
Ubuntu Security Notice USN-4308-1
March 19, 2020

twisted vulnerabilities
==========================================================================

A security issue affects these releases of Ubuntu and its derivatives:

- Ubuntu 19.10
- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS

Summary:

Several security issues were fixed in Twisted.

Software Description:
- twisted: Event-based framework for internet applications

Details:

it was discovered that Twisted incorrectly validated or sanitized certain
URIs or HTTP methods. A remote attacker could use this issue to inject
invalid characters and possibly perform header injection attacks.
(CVE-2019-12387)

It was discovered that Twisted incorrectly verified XMPP TLS certificates.
A remote attacker could possibly use this issue to perform a
man-in-the-middle attack and obtain sensitive information. (CVE-2019-12855)

It was discovered that Twisted incorrectly handled HTTP/2 connections. A
remote attacker could possibly use this issue to cause Twisted to hang or
consume resources, leading to a denial of service. This issue only affected
Ubuntu 18.04 LTS and Ubuntu 19.10. (CVE-2019-9512, CVE-2019-9514,
CVE-2019-9515)

Jake Miller and ZeddYu Lu discovered that Twisted incorrectly handled
certain content-length headers. A remote attacker could possibly use this
issue to perform HTTP request splitting attacks. (CVE-2020-10108,
CVE-2020-10109)

Update instructions:

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

Ubuntu 19.10:
  python-twisted                  18.9.0-3ubuntu1.1
  python-twisted-bin              18.9.0-3ubuntu1.1
  python-twisted-web              18.9.0-3ubuntu1.1
  python3-twisted                 18.9.0-3ubuntu1.1
  python3-twisted-bin             18.9.0-3ubuntu1.1

Ubuntu 18.04 LTS:
  python-twisted                  17.9.0-2ubuntu0.1
  python-twisted-bin              17.9.0-2ubuntu0.1
  python-twisted-web              17.9.0-2ubuntu0.1
  python3-twisted                 17.9.0-2ubuntu0.1
  python3-twisted-bin             17.9.0-2ubuntu0.1

Ubuntu 16.04 LTS:
  python-twisted                  16.0.0-1ubuntu0.4
  python-twisted-bin              16.0.0-1ubuntu0.4
  python-twisted-web              16.0.0-1ubuntu0.4
  python3-twisted                 16.0.0-1ubuntu0.4

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

References:
  https://usn.ubuntu.com/4308-1
  CVE-2019-12387, CVE-2019-12855, CVE-2019-9512, CVE-2019-9514,
  CVE-2019-9515, CVE-2020-10108, CVE-2020-10109

Package Information:
  https://launchpad.net/ubuntu/+source/twisted/18.9.0-3ubuntu1.1
  https://launchpad.net/ubuntu/+source/twisted/17.9.0-2ubuntu0.1
  https://launchpad.net/ubuntu/+source/twisted/16.0.0-1ubuntu0.4