CVE Catalog

CVE-2026-80929

HighCVSS 7.8
Published: Updated: Translated: NVD NIST

Exploitation Probability (EPSS)

Low risk
0.16%

5th percentile - higher than 5% of all known CVEs

Summary

In the Linux kernel, the "cad_pid" sysctl entry is global and kill_cad_pid() is only used in the root namespace. However, due to pid_table_root_permissions(), a non-root user can unshare pid/user namespaces and modify it from the child namespace, which is wrong.

Risk Assessment

A non-root user can modify the global cad_pid sysctl from a child namespace, potentially affecting system behavior. This violates expected permissions.

Recommendation

Update the Linux kernel to a version with the fix that moves the "cad_pid" entry from pid_table[] to kern_reboot_table[], ensuring only GLOBAL_ROOT_UID can read/modify it.

Related vulnerabilities

Original NVD description (English source)

In the Linux kernel, the following vulnerability has been resolved: sysctl: move the "cad_pid" entry from pid_table[] to kern_reboot_table[] cad_pid is global, and kill_cad_pid() is only used in the root namespace. However, due to pid_table_root_permissions(), a non-root user can unshare pid/user namespaces and modify it from the child namespace. This makes no sense and is simply wrong. Move it to kern_reboot_table[] where it logically belongs; this ensures that only GLOBAL_ROOT_UID can read/modify this sysctl. Note that this patch doesn't preserve "#ifdef CONFIG_PROC_SYSCTL" around the "cad_pid"; CONFIG_PROC_SYSCTL selects CONFIG_SYSCTL, so it is always set when kern_reboot_table[] is compiled.

Vulnerability data from NVD (NIST) · CISA KEV · EPSS