Vulnerability Description
In the Linux kernel, the following vulnerability has been resolved: netdev-genl: report NAPI thread PID in the caller's pid namespace netdev_nl_napi_fill_one() reports the NAPI kthread PID in NETDEV_A_NAPI_PID using task_pid_nr(), which returns the PID in the initial pid namespace. NETDEV_CMD_NAPI_GET does not have GENL_ADMIN_PERM and the netdev genl family is netnsok, so a caller in a child pid namespace can issue it. That caller then sees the kthread's global PID, even though the kthread is not visible in its pid namespace, where the value should be 0. Translate the PID through the caller's pid namespace, the same way commit 3799c2570982 ("io_uring/fdinfo: translate SqThread PID through caller's pid_ns") did for the io_uring SQPOLL thread. The doit and dumpit paths both run synchronously in the caller's context, so task_active_pid_ns(current) is the caller's pid namespace.
References
- https://git.kernel.org/stable/c/1f24c0d01db214c9e661915e9972404c96ca73c0
- https://git.kernel.org/stable/c/5e4c8e08ce95730c87d6ada0bdbe1131a3c06393
- https://git.kernel.org/stable/c/fb18095389fe81f140d39585a2624aca9d42227e
- https://git.kernel.org/stable/c/fd750b694f1f9e1ecb8ca19314e4e21edbb15f42
FAQ
What is CVE-2026-72127?
CVE-2026-72127 is a documented vulnerability. In the Linux kernel, the following vulnerability has been resolved: netdev-genl: report NAPI thread PID in the caller's pid namespace netdev_nl_napi_fill_one() reports the NAPI kthread PID in NETDEV...
How severe is CVE-2026-72127?
CVSS scoring is not yet available for CVE-2026-72127. Check NVD for updates.
Is there a patch for CVE-2026-72127?
Check the references section above for vendor advisories and patch information. Review vendor security bulletins for remediation guidance.