CVE-2026-64036 - CERT CVE
ID CVE-2026-64036
Sažetak In the Linux kernel, the following vulnerability has been resolved: cgroup/rstat: validate cpu before css_rstat_cpu() access css_rstat_updated() is exposed as a BPF kfunc and accepts a caller-provided cpu argument. The function uses cpu for per-cpu rstat lookups without checking whether it refers to a valid possible CPU. A BPF iter/cgroup program with CAP_BPF and CAP_PERFMON can pass an invalid cpu value. On an unfixed UBSCAN_BOUNDS test kernel, cpu == 0x7fffffff triggers: UBSAN: array-index-out-of-bounds in kernel/cgroup/rstat.c:31:9 index 2147483647 is out of range for type 'long unsigned int [64]' Call Trace: css_rstat_updated bpf_iter_run_prog cgroup_iter_seq_show bpf_seq_read Add cpu validation to the BPF-facing css_rstat_updated() kfunc and move the common implementation to __css_rstat_updated() for in-kernel callers.
Reference
CVSS
Base: 7.8
Impact: 5.9
Exploitability:1.8
Pristup
VektorSloženostAutentikacija
LOCAL LOW LOW
Impact
PovjerljivostCjelovitostDostupnost
HIGH HIGH HIGH
CVSS vektor CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
Zadnje važnije ažuriranje 20-07-2026 - 15:17
Objavljeno 19-07-2026 - 16:17