This USN details two medium-severity systemd vulnerabilities: CVE-2026-40226 (CVSS 6.4) is a local container escape in systemd-nspawn via mishandled configuration files, affecting systemd versions 233 through 257.11, 258 through 258.5, and 259 through 259.3, fixed in versions 257.12, 258.6, and 259.4 respectively. CVE-2023-7008 (CVSS 5.9) is a DNSSEC validation flaw in systemd-resolved allowing DNS manipulation, specifically affecting Ubuntu 22.04 LTS. The standard remediation is a system update followed by a reboot.
Ubuntu Security Notices USN-8402-1 USN-8402-1: systemd vulnerabilities Publication date 8 June 2026 Overview Several security issues were fixed in systemd. Releases 25.10 24.04 LTS 22.04 LTS Open side navigation Close side navigation Packages Details Update instructions References Packages systemd - system and service manager Details It was discovered that systemd-nspawn incorrectly handled certain optional configuration files. A local attacker could possibly use this issue to escape to the host system and execute arbitrary code. ( CVE-2026-40226 ) It was discovered that systemd-resolved incorrectly validated DNSSEC records for signed domains. An attacker could possibly use this issue to manipulate DNS records. This issue only affected Ubuntu 22.04 LTS. ( CVE-2023-7008 ) It was discovered that systemd-nspawn incorrectly handled certain optional configuration files. A local attacker could possibly use this issue to escape to the host system and execute arbitrary code. ( CVE-2026-40226 ) It was discovered that systemd-resolved incorrectly validated DNSSEC records for signed domains. An attacker could possibly use this issue to manipulate DNS records. This issue only affected Ubuntu 22.04 LTS. ( CVE-2023-7008 ) Update instructions After a standard system update you need to reboot your computer to make all the necessary changes. Learn more about how to get the fixes. The problem can be corrected by updating your system to the following package versions: Ubuntu Release Package Version 25.10 questing libsystemd0 – 257.9-0ubuntu2.5 libudev1 – 257.9-0ubuntu2.5 systemd – 257.9-0ubuntu2.5 udev – 257.9-0ubuntu2.5 24.04 LTS noble libsystemd0 – 255.4-1ubuntu8.16 libudev1 – 255.4-1ubuntu8.16 systemd – 255.4-1ubuntu8.16 udev – 255.4-1ubuntu8.16 22.04 LTS jammy libnss-resolve – 249.11-0ubuntu3.21 libsystemd0 – 249.11-0ubuntu3.21 libudev1 – 249.11-0ubuntu3.21 systemd – 249.11-0ubuntu3.21 udev – 249.11-0ubuntu3.21 Reduce your security exposure Ubuntu Pro provides ten-year security coverage to 25,000+ packages in Main and Universe repositories, and it is free for up to five machines. Get Ubuntu Pro References CVE-2026-40226 CVE-2023-7008 CVE-2026-40226 CVE-2023-7008