Description
A vulnerability was discovered in gdm before 3.31.4. When timed login is enabled in configuration, an attacker could bypass the lock screen by selecting the timed login user and waiting for the timer to expire, at which time they would gain access to the logged-in user's session.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| The Gnome Projectr | gdm | 3.31.4 | — |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | gdm3 | 3.30.2-3 | — |
| Debian 13 | gdm3 | 3.30.2-3 | — |
| Debian 12 | gdm3 | 3.30.2-3 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | gdm3 | 3.28.3-0ubuntu18.04.4 | USN-3892-1 |
| Ubuntu 16.04 LTS | gdm3 | No fix yet | — |
Red Hat
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| RHEL 8 | LibRaw +1 | 0.19.5-1.el8 | RHSA-2020:1766 |
| RHEL 8 | accountsservice +2 | 0.6.50-8.el8 | RHSA-2020:1766 |
| RHEL 8 | appstream-data | 8-20191129.el8 | RHSA-2020:1766 |
| RHEL 8 | baobab | 3.28.0-4.el8 | RHSA-2020:1766 |
| RHEL 8 | clutter +2 | 1.26.2-8.el8 | RHSA-2020:1766 |
| RHEL 8 | evince +3 | 3.28.4-4.el8 | RHSA-2020:1766 |
| RHEL 8 | gdm | 1:3.28.3-29.el8 | RHSA-2020:1766 |
| RHEL 8 | gjs +1 | 1.56.2-4.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-boxes | 3.28.5-8.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-control-center +1 | 3.28.2-19.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-menus +1 | 3.13.3-11.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-online-accounts +1 | 3.28.2-1.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-remote-desktop | 0.1.6-8.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-session +2 | 3.28.1-8.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-settings-daemon | 3.32.0-9.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-shell | 3.32.2-14.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-software +1 | 3.30.6-3.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-terminal +1 | 3.28.3-1.el8 | RHSA-2020:1766 |
| RHEL 8 | gnome-tweaks | 3.28.1-7.el8 | RHSA-2020:1766 |
| RHEL 8 | gsettings-desktop-schemas +1 | 3.32.0-4.el8 | RHSA-2020:1766 |
| RHEL 8 | gtk3 +3 | 3.22.30-5.el8 | RHSA-2020:1766 |
| RHEL 8 | gvfs +10 | 1.36.2-8.el8 | RHSA-2020:1766 |
| RHEL 8 | libvncserver +1 | 0.9.11-14.el8 | RHSA-2020:1766 |
| RHEL 8 | libxslt +1 | 1.1.32-4.el8 | RHSA-2020:1766 |
| RHEL 8 | mozjs52 +1 | 52.9.0-2.el8 | RHSA-2020:1766 |
| RHEL 8 | mozjs60 +1 | 60.9.0-4.el8 | RHSA-2020:1766 |
| RHEL 8 | mutter +1 | 3.32.2-34.el8 | RHSA-2020:1766 |
| RHEL 8 | nautilus +2 | 3.28.1-12.el8 | RHSA-2020:1766 |
| RHEL 8 | vala +1 | 0.40.19-1.el8 | RHSA-2020:1766 |
| RHEL 8 | vinagre | 3.22.0-21.el8 | RHSA-2020:1766 |
AlmaLinux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| AlmaLinux 8 | accountsservice-devel | 0.6.50-8.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | baobab | 3.28.0-4.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | clutter +2 | 1.26.2-8.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | gjs-devel | 1.56.2-4.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | gnome-menus +1 | 3.13.3-11.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | gnome-tweaks | 3.28.1-7.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | mozjs52 +1 | 52.9.0-2.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | mozjs60 +1 | 60.9.0-4.el8 | ALSA-2020:1766 |
| AlmaLinux 8 | vala +1 | 0.40.19-1.el8 | ALSA-2020:1766 |
Rocky Linux
Errata ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Rocky Linux 8 | baobab | 3.28.0-4.el8 | RLSA-2020:1766 |
| Rocky Linux 8 | clutter | 1.26.2-8.el8 | RLSA-2020:1766 |
| Rocky Linux 8 | gnome-menus | 3.13.3-11.el8 | RLSA-2020:1766 |
| Rocky Linux 8 | gnome-tweaks | 3.28.1-7.el8 | RLSA-2020:1766 |
| Rocky Linux 8 | mozjs52 | 52.9.0-2.el8 | RLSA-2020:1766 |
| Rocky Linux 8 | mozjs60 | 60.9.0-4.el8 | RLSA-2020:1766 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | gdm | 3.26.2.1-13.19.2 | SUSE-SU-2019:0527-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | gdm | 3.38.2-2.7 | openSUSE-SU-2024:10780-1 |
Oracle Linux
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Oracle Linux 8 | LibRaw +1 | 0.19.5-1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | accountsservice +2 | 0.6.50-8.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | appstream-data | 8-20191129.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | clutter +2 | 1.26.2-8.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | evince +3 | 3.28.4-4.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gdm | 1:3.28.3-29.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gjs +1 | 1.56.2-4.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-boxes | 3.28.5-8.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-control-center +1 | 3.28.2-19.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-menus +1 | 3.13.3-11.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-online-accounts +1 | 3.28.2-1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-remote-desktop | 0.1.6-8.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-session +2 | 3.28.1-8.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-settings-daemon | 3.32.0-9.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-shell | 3.32.2-14.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-software +1 | 3.30.6-3.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-terminal +1 | 3.28.3-1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gnome-tweaks | 3.28.1-7.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gsettings-desktop-schemas +1 | 3.32.0-4.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | gtk3 +3 | 3.22.30-5.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | libvncserver +1 | 0.9.11-14.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | libxslt +1 | 1.1.32-4.0.1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | mozjs52 +1 | 52.9.0-2.0.1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | mozjs60 +1 | 60.9.0-4.0.1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | mutter +1 | 3.32.2-34.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | nautilus +2 | 3.28.1-12.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | vala +1 | 0.40.19-1.el8 | ELSA-2020-1766 |
| Oracle Linux 8 | vinagre | 3.22.0-21.el8 | ELSA-2020-1766 |
Advisories 8
- ALSA-2020:1766 Moderate: GNOME security, bug fix, and enhancement update AlmaLinux Security Advisories · Nov 5, 2026
- WID-SEC-2026-4026 Red Hat OpenShift: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 18, 2026
- RHSA-2020:1766 Red Hat Security Advisory: GNOME security, bug fix, and enhancement update Red Hat Security Advisories (RHSA) · Jun 27, 2026
- USN-3892-1 gdm3 vulnerability Ubuntu Security Notices (USN) · Apr 27, 2026
- RLSA-2020:1766 Moderate: GNOME security, bug fix, and enhancement update Rocky Linux Security Advisories · Feb 4, 2026
- openSUSE-SU-2024:10780-1 gdm-3.38.2-2.7 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
- SUSE-SU-2019:0527-1 Security update for gdm SUSE / openSUSE Security Updates · May 2, 2025
- ELSA-2020-1766 Moderate: GNOME security, bug fix, and enhancement update (Oracle Linux 8) Oracle Linux Security Advisories (ELSA) · May 5, 2020
References
- USN-3892-1 vendor-advisory
- https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2019-3825