Seven stable kernels patch a critical flaw in the Linux network stack

Greg Kroah-Hartman has announced the release of the stable Linux kernels 7.2.11, 6.18.57, 6.12.113, 6.6.159, 6.1.190, 5.15.223, and 5.10.272. The updates land across all seven maintained branches at once — a sign that at least some of the included fixes carry real weight.

The headline item is a critical vulnerability tracked as CVE-2026-99999. The flaw lives in skb_checksum_help(), the function responsible for handling packet checksums in the kernel.

According to patch author Michael S. Tsirkin, an IPv4 packet carrying bad checksum metadata could "corrupt the network header and cause a bunch of mischief." Behind that deliberately understated phrasing sits memory corruption in the kernel's network stack — precisely the kind of bug that tends to prove exploitable.

As usual in such cases, all users are advised to upgrade. The breadth of affected branches — from the recent 7.2 all the way back to the long-maintained 5.10 — means the update is relevant to virtually any system running a supported stable kernel.

Source: LWN.net