CVE-2019-18684

Publication date 4 November 2019

Last updated 24 July 2024

Ubuntu priority

Cvss 3 Severity Score

** DISPUTED ** Sudo through 1.8.29 allows local users to escalate to root if they have write access to file descriptor 3 of the sudo process. This occurs because of a race condition between determining a uid, and the setresuid and openat system calls. The attacker can write "ALL ALL=(ALL) NOPASSWD:ALL" to /proc/#####/fd/3 at a time when Sudo is prompting for a password. NOTE: This has been disputed due to the way Linux /proc works. It has been argued that writing to /proc/#####/fd/3 would only be viable if you had permission to write to /etc/sudoers. Even with write permission to /proc/#####/fd/3, it would not help you write to /etc/sudoers.

Read the notes from the security team

Status

Show unmaintained releases

Package	Ubuntu Release	Status
sudo	19.10 eoan	Not affected
	19.04 disco	Not affected
	18.04 LTS bionic	Not affected
	16.04 LTS xenial	Not affected
	14.04 LTS trusty	Not affected

Notes

mdeslaur

this isn't an issue and was rejected by upstream

Severity score breakdown

Parameter	Value
Base score	7.0 · High
Attack vector	Local
Attack complexity	High
Privileges required	Low
User interaction	None
Scope	Unchanged
Confidentiality	High
Integrity impact	High
Availability impact	High
Vector	CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H