Lei Wang and Li Fubang discovered that runC incorrectly handled masked paths. An attacker could possibly replace a container's /dev/null with a symlink to some other procfs file and possibly escape a container. ( CVE-2025-31133 ) Lei Wang and Li Fubang discovered that runC incorrectly handled the /dev/console bind-mounts. An attacker could potentially exploit this issue to build-mount a symlink and escape a container. ( CVE-2025-52565 ) Li Fubang and Tõnis Tiigi discovered that the fix for CVE-2019-16884 was incomplete. An attacker could possibly use this issue to cause a denial of service or escape the container. ( CVE-2025-52881 )
Lei Wang and Li Fubang discovered that runC incorrectly handled masked paths. An attacker could possibly replace a container's /dev/null with a symlink to some other procfs file and possibly escape a container. ( CVE-2025-31133 )
Lei Wang and Li Fubang discovered that runC incorrectly handled the /dev/console bind-mounts. An attacker could potentially exploit this issue to build-mount a symlink and escape a container. ( CVE-2025-52565 )
Li Fubang and Tõnis Tiigi discovered that the fix for CVE-2019-16884 was incomplete. An attacker could possibly use this issue to cause a denial of service or escape the container. ( CVE-2025-52881 )
Lei Wang and Li Fubang discovered that runC incorrectly handled masked paths. An attacker could possibly replace a container's /dev/null with a symlink to some other procfs file and possibly escape a container. ( CVE-2025-31133 ) Lei Wang and Li Fubang discovered that runC incorrectly handled the /dev/console bind-mounts. An attacker could potentially exploit this issue to build-mount a symlink and escape a container. ( CVE-2025-52565 ) Li Fubang and Tõnis Tiigi discovered that the fix for CVE-2019-16884 was incomplete. An attacker could possibly use this issue to cause a denial of service or escape the container. ( CVE-2025-52881 )
Lei Wang and Li Fubang discovered that runC incorrectly handled masked paths. An attacker could possibly replace a container's /dev/null with a symlink to some other procfs file and possibly escape a container. ( CVE-2025-31133 )
Lei Wang and Li Fubang discovered that runC incorrectly handled the /dev/console bind-mounts. An attacker could potentially exploit this issue to build-mount a symlink and escape a container. ( CVE-2025-52565 )
Li Fubang and Tõnis Tiigi discovered that the fix for CVE-2019-16884 was incomplete. An attacker could possibly use this issue to cause a denial of service or escape the container. ( CVE-2025-52881 )
This update uses a new upstream release, which includes additional bug fixes. In general, a standard system update will make all the necessary changes.
The problem can be corrected by updating your system to the following package versions:
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.
The full story
This article is one source in a clustered incident — the cluster page carries the summary, timeline and every other outlet covering it.
