Description
The daemon in GDM through 3.29.1 does not properly unexport display objects from its D-Bus interface when they are destroyed, which allows a local attacker to trigger a use-after-free via a specially crafted sequence of D-Bus method calls, resulting in a denial of service or potential code execution.
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 | 3.28.2-4 | — |
| Debian 13 | gdm3 | 3.28.2-4 | — |
| Debian 12 | gdm3 | 3.28.2-4 | — |
| Debian 9 | gdm3 | 3.22.3-3+deb9u2 | DSA-4270-1 |
| Debian 8 | gdm3 | 3.14.1-7+deb8u1 | DLA-1494-1 |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 18.04 LTS | gdm3 | 3.28.2-0ubuntu1.4 | USN-3737-1 |
| Ubuntu 16.04 LTS | gdm3 | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 | gdm | 3.26.2.1-13.9.1 | SUSE-SU-2018:2771-1 |
| SLES 12 SP3 | gdm | 3.10.0.1-54.6.3 | SUSE-SU-2018:2527-1 |
Show 1 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP3 | gdm | 3.10.0.1-54.6.3 | SUSE-SU-2018:2527-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | gdm | 3.38.2-2.7 | openSUSE-SU-2024:10780-1 |
Advisories 6
- USN-3737-1 gdm3 vulnerability Ubuntu Security Notices (USN) · Apr 27, 2026
- DSA-4270-1 gdm3 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- DLA-1494-1 gdm3 - security update Debian Security (DSA / DLA) · Mar 9, 2026
- SUSE-SU-2018:2771-1 Security update for gdm SUSE / openSUSE Security Updates · 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-2018:2527-1 Security update for gdm SUSE / openSUSE Security Updates · Feb 4, 2026
References
- [debian-lts-announce] 20180905 [SECURITY] [DLA 1494-1] gdm3 security update mailing-list
- https://gitlab.gnome.org/GNOME/gdm/issues/401
- USN-3737-1 vendor-advisory
- DSA-4270 vendor-advisory
- 105179 vdb-entry