CVE-2025-68742

Updated on 24 Dec 2025

Severity

5.8 Medium severity

Details

CVSS score
5.8

Overview

About vulnerability

In the Linux kernel, the following vulnerability has been resolved: bpf: Fix invalid prog->stats access when update_effective_progs fails Syzkaller triggers an invalid memory access issue following fault injection in update_effective_progs. The issue can be described as follows: __cgroup_bpf_detach update_effective_progs compute_effective_progs bpf_prog_array_alloc <– fault inject purge_effective_progs /* change to dummy_bpf_prog / array->items[index] = &dummy_bpf_prog.prog —softirq start— __do_softirq … __cgroup_bpf_run_filter_skb __bpf_prog_run_save_cb bpf_prog_run stats = this_cpu_ptr(prog->stats) / invalid memory access */ flags = u64_stats_update_begin_irqsave(&stats->syncp) —softirq end— static_branch_dec(&cgroup_bpf_enabled_key[atype]) The reason is that fault injection caused update_effective_progs to fail and then changed the original prog into dummy_bpf_prog.prog in purge_effective_progs. Then a softirq came, and accessing the members of dummy_bpf_prog.prog in the softirq triggers invalid mem access. To fix it, skip updating stats when stats is NULL. An invalid memory access vulnerability was found in the Linux kernel’s BPF cgroup subsystem. When update_effective_progs fails due to allocation failure (such as from fault injection), the code replaces the program with dummy_bpf_prog. If a softirq occurs and attempts to run the BPF filter, accessing dummy_bpf_prog.prog->stats triggers an invalid memory access because the dummy program’s stats pointer is NULL.

Details

KernelCare state

Live-patch status from KernelCare for each operating system.

Operating system Status Covered kernels
Amazon Linux 2023 Planned
Debian 12 Planned
Debian 13 Will Not Fix
Ubuntu 24.04 Will Not Fix
41 kernels
  • 6.8.0-35.35
  • 6.8.0-38.38
  • 6.8.0-36.36
  • 6.8.0-39.39
  • 6.8.0-40.40
  • 6.8.0-41.41
  • 6.8.0-44.44
  • 6.8.0-45.45
  • 6.8.0-31.31
  • 6.8.0-47.47
  • 6.8.0-48.48
  • 6.8.0-49.49
  • 6.8.0-50.51
  • 6.8.0-51.52
  • 6.8.0-52.53
  • 6.8.0-54.56
  • 6.8.0-55.57
  • 6.8.0-53.55
  • 6.8.0-56.58
  • 6.8.0-57.59
  • 6.8.0-58.60
  • 6.8.0-59.61
  • 6.8.0-60.63
  • 6.8.0-62.65
  • 6.8.0-63.66
  • 6.8.0-64.67
  • 6.8.0-71.71
  • 6.8.0-78.78
  • 6.8.0-79.79
  • 6.8.0-84.84
  • 6.8.0-85.85
  • 6.8.0-83.83
  • 6.8.0-86.87
  • 6.8.0-87.88
  • 6.8.0-88.89
  • 6.8.0-90.91
  • 6.8.0-94.96
  • 6.8.0-100.100
  • 6.8.0-101.101
  • 6.8.0-106.106
  • 6.8.0-107.107
Ubuntu 24.04 AWS Planned