Ubuntu OverlayFS Local Privesc Vulnerability - Safe Security
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Ubuntu OverlayFS Local Privesc Vulnerability

CVE-2021-3493 is an Ubuntu-specific Linux kernel overlayfs flaw involving improper validation of application file system capabilities to user namespaces.

A local attacker could use this to gain elevated privileges, due to a patch carried in Ubuntu to allow unprivileged overlayfs mounts.

Key Pointers:

  • Understanding important key points used throughout the paper
  • The severity and scope of impact of this vulnerability
  • Learning about the mitigations for different Ubuntu versions
  • Setting up the lab environment and demonstrating the exploitation method