USN-4616-1: AccountsService vulnerabilities

Releases

• Ubuntu 20.10
• Ubuntu 20.04 LTS
• Ubuntu 18.04 ESM
• Ubuntu 16.04 ESM

Packages

• accountsservice - query and manipulate user account information

Details

Kevin Backhouse discovered that AccountsService incorrectly dropped
privileges. A local user could possibly use this issue to cause
AccountsService to crash or hang, resulting in a denial of service.
(CVE-2020-16126)

Kevin Backhouse discovered that AccountsService incorrectly handled reading
.pam_environment files. A local user could possibly use this issue to cause
AccountsService to crash or hang, resulting in a denial of service. This
issue only affected Ubuntu 20.04 LTS and Ubuntu 20.10. (CVE-2020-16127)

Matthias Gerstner discovered that AccountsService incorrectly handled
certain path checks. A local attacker could possibly use this issue to
read arbitrary files. This issue only affected Ubuntu 16.04 LTS and Ubuntu
18.04 LTS. (CVE-2018-14036)

Update instructions

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

Ubuntu 20.10

• accountsservice - 0.6.55-0ubuntu13.2
• libaccountsservice0 - 0.6.55-0ubuntu13.2

Ubuntu 20.04

• accountsservice - 0.6.55-0ubuntu12~20.04.4
• libaccountsservice0 - 0.6.55-0ubuntu12~20.04.4

Ubuntu 18.04

• accountsservice - 0.6.45-1ubuntu1.3
• libaccountsservice0 - 0.6.45-1ubuntu1.3

Ubuntu 16.04

• accountsservice - 0.6.40-2ubuntu11.6
• libaccountsservice0 - 0.6.40-2ubuntu11.6

After a standard system update you need to reboot your computer to make
all the necessary changes.

References

• CVE-2020-16126
• CVE-2018-14036
• CVE-2020-16127

Related notices

• USN-4616-2