(https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2019-13272): 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. Gentoo Security Padawan (domhnall)
Fixed in kernel releases: [From IRC]: <gregkh> 4.4.185 4.9.185 4.14.133 4.19.58 5.1.17 5.2 gentoo-sources as above. Genpatches: - 4.4.186 - 4.9.186 - 4.14.142 - 4.19.59 - 5.1.17