GhostLock: A 15-Year-Old Stack Use-After-Free Vulnerability in Linux

GhostLock designates a use-after-free vulnerability in the Linux kernel's I/O stack that remained undetected across all major Linux distributions for roughly 15 years. A use-after-free condition occurs when memory is accessed after it has been freed, potentially allowing attackers to read sensitive data, corrupt kernel structures, or achieve arbitrary code execution with elevated privileges.

The vulnerability's longevity across entire distribution ecosystems underscores how subtle kernel-level memory errors can evade detection despite broad security testing and auditing efforts. The flaw resided in core I/O handling code—infrastructure used universally across Linux systems—making it a systemic risk to deployed infrastructure, container platforms, and cloud environments.

Research published by Nebusec identifies the technical root cause and exploitation vectors as part of broader kernel stack analysis. The discovery prompts kernel maintainers and distribution vendors to issue patches and establish mitigations, though the extent and timeline of rollout across supported kernel versions remain subject to individual vendor release cycles.