Description
In systemd 223 through 235, a remote DNS server can respond with a custom crafted DNS NSEC resource record to trigger an infinite loop in the dns_packet_read_type_window() function of the 'systemd-resolved' service and cause a DoS of the affected service.
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 | systemd | 235-3 | — |
| Debian 13 | systemd | 235-3 | — |
| Debian 12 | systemd | 235-3 | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 16.04 LTS | systemd | 229-4ubuntu21.1 | USN-3558-1 |
| Ubuntu 14.04 LTS | systemd | 204-5ubuntu20.26 | USN-3558-1 |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 12 SP3 | systemd | 228-150.29.1 | SUSE-SU-2018:0299-1 |
| SLES 12 SP2 | systemd | 228-150.29.1 | SUSE-SU-2018:0299-1 |
Show 2 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 12 SP3 | systemd | 228-150.29.1 | SUSE-SU-2018:0299-1 |
| SLES for SAP 12 SP2 | systemd | 228-150.29.1 | SUSE-SU-2018:0299-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | systemd | 249.4-2.2 | openSUSE-SU-2024:11420-1 |
Advisories 3
- USN-3558-1 systemd vulnerabilities Ubuntu Security Notices (USN) · Apr 22, 2026
- SUSE-SU-2018:0299-1 Security update for systemd SUSE / openSUSE Security Updates · Feb 4, 2026
- openSUSE-SU-2024:11420-1 libsystemd0-249.4-2.2 on GA media SUSE / openSUSE Security Updates · Feb 4, 2026
References
- 1039662 vdb-entry
- 101600 vdb-entry
- https://github.com/systemd/systemd/pull/7184
- USN-3558-1 vendor-advisory
- https://bugs.launchpad.net/ubuntu/+source/systemd/+bug/1725351