Re: CVE-2019-18634: buffer overflow in sudo when pwfeedback is enabled

["Todd C. Miller" <Todd.Miller () sudo ws>]

On Thu, 30 Jan 2020 11:23:28 -0700, "Todd C. Miller" wrote:

> Sudo versions affected:
>
> Sudo versions 1.7.1 to 1.8.30 inclusive are affected but only if
> the "pwfeedback" option is enabled in sudoers.

It turns out a change in EOF handling introduced in sudo 1.8.26
prevents exploitation of the bug.  The EOF character is also
initialized to 0 and sudo 1.8.26 checks for EOF before it checks
for the kill character.

This means that the bug actually affects sudo versions 1.7.1 to
1.8.25p1 inclusive.

Sorry for the oversight.  I've updated the affected versions in
https://www.sudo.ws/alerts/pwfeedback.html

 - todd