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[ CVE-2019-13272 · Published 17 Jul 2019 ]

Linux Kernel Improper Privilege Management Vulnerability

Exploited · CISA KEV CVSS 7.8 EPSS 52%Fix available

[ Why it matters ]Priority signals

  • Exploited in the wild: on CISA's Known Exploited Vulnerabilities list since 2021-12-10
  • EPSS: 52% chance of exploitation in the next 30 days (higher than 99% of CVEs)

[ Description ]Official description

In the Linux kernel before 5.1.17, ptrace_link in kernel/ptrace.c mishandles the recording of the credentials of a process that wants to create a ptrace relationship, which allows local users to obtain root access by leveraging certain scenarios with a parent-child process relationship, where a parent drops privileges and calls execve (potentially allowing control by an attacker). One contributing factor is an object lifetime issue (which can also cause a panic). Another contributing factor is incorrect marking of a ptrace relationship as privileged, which is exploitable through (for example) Polkit's pkexec helper with PTRACE_TRACEME. NOTE: SELinux deny_ptrace might be a usable workaround in some environments.

CISA: Kernel/ptrace.c in Linux kernel mishandles contains an improper privilege management vulnerability that allows local users to obtain root access.

[ Fixes ]Fixes and patches

CISA required action (US federal deadline 10 Jun 2022): Apply updates per vendor instructions.

[ References ]References