CVE-2025-68742

Description

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.

Statement

This flaw was discovered via syzkaller with fault injection. The vulnerability requires a specific race condition where a BPF program update fails and a softirq runs the cgroup BPF filter before cleanup completes. While the timing requirements make this difficult to exploit reliably, the invalid memory access can cause kernel crashes.

Common Vulnerability Scoring System (CVSS) Score Details

Info alert:Important note

CVSS scores for open source components depend on vendor-specific factors (e.g. version or build chain). Therefore, Red Hat's score and impact rating can be different from NVD and other vendors. Red Hat remains the authoritative CVE Naming Authority (CNA) source for its products and services (see Red Hat classifications).

The following CVSS metrics and score provided are preliminary and subject to review.

CVSS v3 Score Breakdown

Red HatNVDcve.org
Base Score5.8N/AN/A
Attack VectorLocalN/AN/A
Attack ComplexityHighN/AN/A
Privileges RequiredLowN/AN/A
User InteractionNoneN/AN/A
ScopeUnchangedN/AN/A
ConfidentialityLowN/AN/A
Integrity ImpactLowN/AN/A
Availability ImpactHighN/AN/A

Vector

Red Hat: CVSS:3.1/AV:L/AC:H/PR:L/UI:N/S:U/C:L/I:L/A:H

Understanding the Weakness (CWE)

Availability

Technical Impact: DoS: Crash, Exit, or Restart

NULL pointer dereferences usually result in the failure of the process unless exception handling (on some platforms) is available and implemented. Even when exception handling is being used, it can still be very difficult to return the software to a safe state of operation.

Integrity,Confidentiality

Technical Impact: Execute Unauthorized Code or Commands; Read Memory; Modify Memory

In rare circumstances, when NULL is equivalent to the 0x0 memory address and privileged code can access it, then writing or reading memory is possible, which may lead to code execution.

Frequently Asked Questions

Want to get errata notifications? Sign up here.