Greg Kroah-Hartman has announced the release of the 6.19.8, 6.18.18, and 6.12.77 stable kernels. Each of these kernels includes a number of important fixes; users are advised to upgrade.

I've been pulling public records on the wave of "age verification" bills moving through US state legislatures. IRS 990 filings, Senate lobbying disclosures, state ethics databases, campaign finance records, corporate registries, WHOIS lookups, Wayback Machine archives. What started as curiosity about who was pushing these bills turned into documenting a coordinated influence operation that, from a privacy standpoint, is building surveillance infrastructure at the operating system level while the company behind it faces zero new requirements for its own platforms.

(See also this article for a look at the California law.)

This "CrackArmor" advisory exposes a confused-deputy flaw allowing unprivileged users to manipulate security profiles via pseudo-files, bypass user-namespace restrictions, and execute arbitrary code within the kernel. These flaws facilitate local privilege escalation to root through complex interactions with tools like Sudo and Postfix, alongside denial-of-service attacks via stack exhaustion and Kernel Address Space Layout Randomization (KASLR) bypasses via out-of-bounds reads.

In 2019, researchers published a way to identify which file-backed pages were being accessed on a system using timing information from the page cache, leading to a handful of unpleasant consequences and a change to the design of the mincore() system call. Discussion at the time led to a number of ad-hoc patches to address the problem. The lack of new page-cache attacks suggested that attempts to fix things in a piecemeal fashion had succeeded. Now, however, Sudheendra Raghav Neela, Jonas Juffinger, Lukas Maar, and Daniel Gruss have found a new set of holes in the Linux kernel's page-cache-timing protections that allow the same general class of attack.