CoreCVE
Back

HIGH

sudo: Privilege escalation via 'Runas' specification with 'ALL' keyword

Published Oct 17, 2019

Description

In Sudo before 1.8.28, an attacker with access to a Runas ALL sudoer account can bypass certain policy blacklists and session PAM modules, and can cause incorrect logging, by invoking sudo with a crafted user ID. For example, this allows bypass of !root configuration, and USER= logging, for a "sudo -u \#$((0xffffffff))" command.

Affected products

Remediation

Red Hat statement

This flaw only affects specific, non-default configurations of sudo, in which sudoers configuration entry allows a user to run a command as any user except root, for example: someuser myhost = (ALL, !root) /usr/bin/somecommand This configuration allows user "someuser" to run somecommand as any other user except root. However, this flaw also allows someuser to run somecommand as root by specifying the target user using the numeric id of -1. Only the specified command can be run, this flaw does NOT allow user to run other commands that those specified in the sudoers configuration. Any other configurations of sudo (including configurations that allow user to run commands as any user including root and configurations that allow user to run command as a specific other user) are NOT affected by this flaw. Red Hat Virtualization Hypervisor includes an affected version of sudo, however the default configuration is not vulnerable to this flaw.

Red Hat mitigation

This vulnerability only affects configurations of sudo that have a runas user list that includes an exclusion of root. The most simple example is: ~~~ someuser ALL=(ALL, !root) /usr/bin/somecommand ~~~ The exclusion is specified using an excalamation mark (!). In this example, the "root" user is specified by name. The root user may also be identified in other ways, such as by user id: ~~~ someuser ALL=(ALL, !#0) /usr/bin/somecommand ~~~ or by reference to a runas alias: ~~~ Runas_Alias MYGROUP = root, adminuser someuser ALL=(ALL, !MYGROUP) /usr/bin/somecommand ~~~ To ensure your sudoers configuration is not affected by this vulnerability, we recommend examining each sudoers entry that includes the `!` character in the runas specification, to ensure that the root user is not among the exclusions. These can be found in the /etc/sudoers file or files under /etc/sudoers.d.

Weaknesses (2)

CWE-267

CWE-755

References (41)

Change history (0)

No recorded changes yet.

Sources
CVE.org / MITRE
Status PUBLISHED
Assigner mitre
Published Oct 17, 2019
Updated Aug 5, 2024
Reserved Jul 27, 2019
Link CVE-2019-14287
CISA Vulnrichment
Updated n/a
NVD
Status Modified
Modified Jun 17, 2026
Link CVE-2019-14287
Red Hat
Severity Important
Public date Oct 14, 2019
Links CVE-2019-14287 - Bugzilla
ENISA EUVD
Assigner n/a
Published n/a
Updated n/a
Exploited since n/a
Link n/a