The following updates has been released for Ubuntu Linux:

USN-3790-1: Requests vulnerability
USN-3792-1: Net-SNMP vulnerability
USN-3793-1: Thunderbird vulnerabilities

USN-3790-1: Requests vulnerability

==========================================================================
Ubuntu Security Notice USN-3790-1
October 15, 2018

requests vulnerability
==========================================================================

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

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Requests could be made to expose sensitive information if it
received a specially crafted HTTP header.

Software Description:
- requests: elegant and simple HTTP library for Python

Details:

It was discovered that Requests incorrectly handled certain HTTP
headers. An attacker could possibly use this issue to access sensitive
information.

Update instructions:

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

Ubuntu 18.04 LTS:
  python-requests 2.18.4-2ubuntu0.1
  python3-requests 2.18.4-2ubuntu0.1

Ubuntu 16.04 LTS:
  python-requests 2.9.1-3ubuntu0.1
  python3-requests 2.9.1-3ubuntu0.1

Ubuntu 14.04 LTS:
  python-requests 2.2.1-1ubuntu0.4
  python-requests-whl 2.2.1-1ubuntu0.4
  python3-requests 2.2.1-1ubuntu0.4

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

References:
  https://usn.ubuntu.com/usn/usn-3790-1
  CVE-2018-18074

Package Information:
  https://launchpad.net/ubuntu/+source/requests/2.18.4-2ubuntu0.1
  https://launchpad.net/ubuntu/+source/requests/2.9.1-3ubuntu0.1
  https://launchpad.net/ubuntu/+source/requests/2.2.1-1ubuntu0.4

USN-3792-1: Net-SNMP vulnerability

==========================================================================
Ubuntu Security Notice USN-3792-1
October 15, 2018

net-snmp vulnerability
==========================================================================

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

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Net-SNMP could be made to crash if it received specially crafted network
traffic.

Software Description:
- net-snmp: SNMP (Simple Network Management Protocol) server and applications

Details:

It was discovered that Net-SNMP incorrectly handled certain certain crafted
packets. A remote attacker could possibly use this issue to cause Net-SNMP
to crash, resulting in a denial of service.

Update instructions:

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

Ubuntu 18.04 LTS:
libsnmp30 5.7.3+dfsg-1.8ubuntu3.1

Ubuntu 16.04 LTS:
libsnmp30 5.7.3+dfsg-1ubuntu4.2

Ubuntu 14.04 LTS:
libsnmp30 5.7.2~dfsg-8.1ubuntu3.3

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

References:
https://usn.ubuntu.com/usn/usn-3792-1
CVE-2018-18065

Package Information:
https://launchpad.net/ubuntu/+source/net-snmp/5.7.3+dfsg-1.8ubuntu3.1
https://launchpad.net/ubuntu/+source/net-snmp/5.7.3+dfsg-1ubuntu4.2
https://launchpad.net/ubuntu/+source/net-snmp/5.7.2~dfsg-8.1ubuntu3.3

USN-3793-1: Thunderbird vulnerabilities

==========================================================================
Ubuntu Security Notice USN-3793-1
October 15, 2018

thunderbird vulnerabilities
==========================================================================

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

- Ubuntu 18.04 LTS
- Ubuntu 16.04 LTS
- Ubuntu 14.04 LTS

Summary:

Several security issues were fixed in Thunderbird.

Software Description:
- thunderbird: Mozilla Open Source mail and newsgroup client

Details:

Multiple security issues were discovered in Thunderbird. If a user were
tricked in to opening a specially crafted website in a browsing context,
an attacker could potentially exploit these to cause a denial of service,
or execute arbitrary code. (CVE-2018-12376, CVE-2018-12377,
CVE-2018-12378)

It was discovered that if a user saved passwords before Thunderbird 58 and
then later set a master password, an unencrypted copy of these passwords
would still be accessible. A local user could exploit this to obtain
sensitive information. (CVE-2018-12383)

A crash was discovered in TransportSecurityInfo used for SSL, which could
be triggered by data stored in the local cache directory. An attacker
could potentially exploit this in combination with another vulnerability
that allowed them to write data to the cache, to execute arbitrary code.
(CVE-2018-12385)

Update instructions:

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

Ubuntu 18.04 LTS:
thunderbird 1:60.2.1+build1-0ubuntu0.18.04.2

Ubuntu 16.04 LTS:
thunderbird 1:60.2.1+build1-0ubuntu0.16.04.4

Ubuntu 14.04 LTS:
thunderbird 1:60.2.1+build1-0ubuntu0.14.04.2

After a standard system update you need to restart Thunderbird to make
all the necessary changes.

References:
https://usn.ubuntu.com/usn/usn-3793-1
CVE-2018-12376, CVE-2018-12377, CVE-2018-12378, CVE-2018-12383,
CVE-2018-12385

Package Information:
https://launchpad.net/ubuntu/+source/thunderbird/1:60.2.1+build1-0ubuntu0.18.04.2
https://launchpad.net/ubuntu/+source/thunderbird/1:60.2.1+build1-0ubuntu0.16.04.4
https://launchpad.net/ubuntu/+source/thunderbird/1:60.2.1+build1-0ubuntu0.14.04.2