Episode 108

Overview

This week we start preparing for 16.04 LTS to transition to Extended Security Maintenance, plus we look at security updates for OpenSSH, Python, the Linux kernel and more, as well as some currently open positions on our team.

This week in Ubuntu Security Updates

28 unique CVEs addressed

[USN-4762-1] OpenSSH vulnerability [00:54]

• 1 CVEs addressed in Focal (20.04 LTS), Groovy (20.10)
  • CVE-2021-28041
• Double free in ssh-agent - so only affects openssh-client and where the ssh-agent socket is able to be accessed by other users etc - on moderns systems the socket is only accessible by the owner so would need to have forwarded the ssh-agent to an attacker controlled host perhaps to be vulnerable..

[USN-4763-1] Pillow vulnerabilities [01:50]

• 8 CVEs addressed in Xenial (16.04 LTS), Bionic (18.04 LTS), Focal (20.04 LTS), Groovy (20.10)
  • CVE-2021-27923
  • CVE-2021-27922
  • CVE-2021-27921
  • CVE-2021-25293
  • CVE-2021-25292
  • CVE-2021-25290
  • CVE-2021-25291
  • CVE-2021-25289
• Python imaging library - uses C libraries like libjpeg for actual image handling so ends up with usual mix of C memory corruption issues - OOB read/write etc - crash, code exec

[USN-4754-3] Python vulnerabilities [02:50]

• 7 CVEs addressed in Bionic (18.04 LTS), Focal (20.04 LTS)
  • CVE-2021-3177
  • CVE-2020-27619
  • CVE-2020-26116
  • CVE-2020-8492
  • CVE-2019-20907
  • CVE-2019-17514
  • CVE-2019-9674
• Good illustration of main vs universe split - multiple python versions in different releases - 2.7 in main X+B, but universe in F+G, 3.5 in X, 3.6 in B, 3.8 in F+G - but we still have 2.7 in universe on those releases as well - so this update addresses the same vulns in universe

[USN-4764-1] GLib vulnerability [04:57]

• 1 CVEs addressed in Xenial (16.04 LTS), Bionic (18.04 LTS), Focal (20.04 LTS), Groovy (20.10)
  • CVE-2021-28153
• g_file_replace() on a dangling symlink would also create the target of the symlink as an empty file (but only if did not already exist)

[USN-4876-1] Linux kernel vulnerabilities [05:49]

• 3 CVEs addressed in Trusty ESM (14.04 ESM), Xenial (16.04 LTS)
  • CVE-2021-3178
  • CVE-2020-36158
  • CVE-2020-29569
• 4.4 (xenial + trusty esm)

[USN-4877-1] Linux kernel vulnerabilities

• 2 CVEs addressed in Trusty ESM (14.04 ESM), Xenial (16.04 LTS), Bionic (18.04 LTS)
  • CVE-2021-3178
  • CVE-2020-36158
• 4.15

[USN-4878-1] Linux kernel vulnerabilities

• 4 CVEs addressed in Bionic (18.04 LTS), Focal (20.04 LTS)
  • CVE-2021-3178
  • CVE-2021-3347
  • CVE-2021-20239
  • CVE-2020-36158
• 5.4

[USN-4879-1] Linux kernel vulnerabilities

• 2 CVEs addressed in Focal (20.04 LTS), Groovy (20.10)
  • CVE-2021-20194
  • CVE-2020-36158
• 5.8
• Marvell wifi driver buffer overflow - could be triggered by a malicious remote device sending a overly long ad-hoc SSID value - DoS, RCE

[USN-4880-1] OpenJPEG vulnerabilities [07:00]

• 5 CVEs addressed in Xenial (16.04 LTS)
  • CVE-2020-27845
  • CVE-2020-27841
  • CVE-2020-27824
  • CVE-2020-27823
  • CVE-2020-27814
• Various memory corruption issues fixed in openjpeg - DoS, RCE etc

Goings on in Ubuntu Security Community

Preparing for 16.04 ESM transition [07:35]

• https://wiki.ubuntu.com/SecurityTeam/ESM/16.04
• https://ubuntu.com/blog/ubuntu-16-04-lts-upgrade-vs-esm
• https://ubuntu.com/engage/16-04-ESM-webinar
  • Lech Sandecki and Rick Harding discuss key concerns for preparing for 16.04 to move to ESM

Hiring [10:17]

AppArmor Security Engineer

• https://canonical.com/careers/2114847/apparmor-security-engineer-remote

Ubuntu Security Engineer

• https://canonical.com/careers/2612092/ubuntu-security-engineer-remote

Security Engineer - Ubuntu

• https://canonical.com/careers/2925180/security-engineer-ubuntu-remote

Get in contact

• [email protected]
• #ubuntu-security on the Libera.Chat IRC network
• ubuntu-hardened mailing list
• Security section on discourse.ubuntu.com
• @ubuntu_sec on twitter