FreeBSD VuXML: Documenting security issues in FreeBSD and the FreeBSD Ports Collection

sudo -- Potential bypass of Runas user restrictions

Affected packages
sudo < 1.8.31


VuXML ID b4e5f782-442d-11ea-9ba9-206a8a720317
Discovery 2020-01-30
Entry 2020-01-30

Todd C. Miller reports:

Sudo's pwfeedback option can be used to provide visual feedback when the user is inputting their password. For each key press, an asterisk is printed. This option was added in response to user confusion over how the standard Password: prompt disables the echoing of key presses. While pwfeedback is not enabled by default in the upstream version of sudo, some systems, such as Linux Mint and Elementary OS, do enable it in their default sudoers files.

Due to a bug, when the pwfeedback option is enabled in the sudoers file, a user may be able to trigger a stack-based buffer overflow. This bug can be triggered even by users not listed in the sudoers file. There is no impact unless pwfeedback has been enabled.


CVE Name CVE-2019-18634