Easy privilege escalation exploit lands for Linux kernels

A Linux privilege-escalation proof-of-concept exploit has been published that, according to the bug hunter who developed it, typically works effortlessly on kernel versions between at least 5.14 and 6.6.14. Running the exploit as a normal user on a vulnerable machine will grant you root access to the box, allowing you to do whatever you want on it. This can be used by rogue insiders or malware already on a computer to cause further damage and problems. This affects Debian, Ubuntu, Red Hat, Fedora, and no doubt other Linux distributions. The flaw finder, known by the handle Notselwyn, issued a highly detailed technical report of the bug this week, and said their exploit had a success rate of 99.4 percent on kernel 6.4.16, for instance. The vulnerability is tracked as CVE-2024-1086. It is rated 7.8 out of 10 in terms of CVSS severity. It was patched at the end of January, updates have been rolling out since then, and if you haven't yet upgraded your vulnerable kernel and local privilege escalation (LPE) is a concern, take a closer look at this thing. "Never had I ever gotten so much joy developing a project, specifically when dropping the first root shell with the bug," Notselwyn enthused. The flaw is a double-free bug in the Linux kernel's netfilter component involving nf_tables. As the US National Vulnerability Database explained: The nft_verdict_init() function allows positive values as drop error within the hook verdict, and hence the nf_hook_slow() function can cause a dou...