New Fragnesia Linux Kernel LPE Grants Root Access via Page Cache Corruption

Fragnesia (CVE-2026-46300) is a Linux local privilege escalation vulnerability in the XFRM ESP-in-TCP subsystem that enables arbitrary writes to the kernel page cache and immediate root access; a PoC has been published, vendors have issued advisories and mitigations (aligned with Dirty Frag mitigations), and a threat actor named “berz0k” is advertising a Linux LPE exploit for sale, elevating the risk of abuse.