CVE-2019-19882
Published: 18 December 2019
shadow 4.8, in certain circumstances affecting at least Gentoo, Arch Linux, and Void Linux, allows local users to obtain root access because setuid programs are misconfigured. Specifically, this affects shadow 4.8 when compiled using --with-libpam but without explicitly passing --disable-account-tools-setuid, and without a PAM configuration suitable for use with setuid account management tools. This combination leads to account management tools (groupadd, groupdel, groupmod, useradd, userdel, usermod) that can easily be used by unprivileged local users to escalate privileges to root in multiple ways. This issue became much more relevant in approximately December 2019 when an unrelated bug was fixed (i.e., the chmod calls to suidusbins were fixed in the upstream Makefile which is now included in the release version 4.8).
Notes
| Author | Note |
|---|---|
| mdeslaur | In Debian and Ubuntu, shadow is compiled with --disable-account-tools-setuid, so this vulnerability is not present |
Priority
Status
| Package | Release | Status |
|---|---|---|
|
shadow Launchpad, Ubuntu, Debian |
bionic |
Not vulnerable
(1:4.5-1ubuntu2)
|
| disco |
Not vulnerable
(1:4.5-1.1ubuntu2)
|
|
| eoan |
Not vulnerable
(1:4.5-1.1ubuntu4)
|
|
| trusty |
Not vulnerable
|
|
| upstream |
Needs triage
|
|
| xenial |
Not vulnerable
(1:4.2-3.1ubuntu5.4)
|
|
|
Patches: upstream: https://github.com/shadow-maint/shadow/commit/edf7547ad5aa650be868cf2dac58944773c12d75 |
||
Severity score breakdown
| Parameter | Value |
|---|---|
| Base score | 7.8 |
| Attack vector | Local |
| Attack complexity | Low |
| Privileges required | Low |
| User interaction | None |
| Scope | Unchanged |
| Confidentiality | High |
| Integrity impact | High |
| Availability impact | High |
| Vector | CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H |