The skb that wasn't freed - the Fragnesia primitive via Open vSwitch
Doyensec publishes a deterministic local privilege-escalation primitive exploiting Open vSwitch skb handling on stock kernels of Arch, Fedora, Debian, Amazon Linux and RHEL—any host with unprivileged user namespaces enabled is exposed.
Summary written by editorial AI · Source link below
TLDR: Exploit . This is a deterministic local privilege escalation affecting the default install of the latest Arch, Fedora, Debian, Amazon Linux and RHEL distributions, having unprivileged user namespaces enabled, openvswitch auto-loading, and a stock kernel carrying the Fragnesia fix. The issue has been public since 08/13/2026 on netdev , and the fix landed in mainline and shipped in stable on 09/04/2026. Introduction Earlier this year a small family of Linux kernel bugs appeared, starting wit
Editorial Analysis
Default-configured Linux servers across the most popular enterprise distributions can be reliably escalated from unprivileged user to root, dramatically raising the stakes of any initial compromise.
Prioritise kernel patching on all affected distributions and restrict unprivileged user namespaces on production hosts where feasible.
A reliable root-escalation exploit affects default Linux installs across major enterprise distributions, requiring urgent patching.
Forward-looking interpretation drafted by editorial AI under human review — not a reproduction of the source. See methodology.
External link — opens at Doyensec in a new tab.
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