CVE-2019-19882

NameCVE-2019-19882
Descriptionshadow 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).
SourceCVE (at NVD; CERT, LWN, oss-sec, fulldisc, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more)

Vulnerable and fixed packages

The table below lists information on source packages.

Source PackageReleaseVersionStatus
shadow (PTS)jessie, jessie (lts)1:4.2-3+deb8u5fixed
stretch (security)1:4.4-4.1+deb9u1fixed
stretch (lts), stretch1:4.4-4.1+deb9u2fixed
buster, buster (lts)1:4.5-1.1+deb10u1fixed
bullseye1:4.8.1-1fixed
bookworm1:4.13+dfsg1-1fixed
sid, trixie1:4.16.0-7fixed

The information below is based on the following data on fixed versions.

PackageTypeReleaseFixed VersionUrgencyOriginDebian Bugs
shadowsourcejessie(not affected)
shadowsourcestretch(not affected)
shadowsourcebuster(not affected)
shadowsource(unstable)1:4.8.1-1unimportant

Notes

https://github.com/shadow-maint/shadow/pull/199
https://bugs.archlinux.org/task/64836
https://bugs.gentoo.org/702252
Debian builds are compiled using --with-libpam and explicitly passing
--disable-account-tools-setuid.
Introduced by: https://github.com/shadow-maint/shadow/commit/edf7547ad5aa650be868cf2dac58944773c12d75 (4.8)
Fixed by: https://github.com/shadow-maint/shadow/commit/66b7bc0dcfda12d7f58eba993bd02872cae1d713 (4.8.1)
[buster] - shadow <not-affected> (Vulnerable code introduced later)
[stretch] - shadow <not-affected> (Vulnerable code introduced later)
[jessie] - shadow <not-affected> (Vulnerable code introduced later)

Search for package or bug name: Reporting problems