VUL-0: CVE-2026-46300: kernel-source: FragNesia attack: another xfrm/esp based local root exploit

Bug 1265209 (CVE-2026-46300) - VUL-0: CVE-2026-46300: kernel-source: FragNesia attack: another xfrm/esp based local root exploit

Fragnesia is a universal Linux local privilege escalation exploit, discovered with V12 by William Bowling with the V12 team. Fragnesia is a member of the Dirty Frag vulnerability class. This is a separate bug in the ESP/XFRM from dirtyfrag which has received its own patch. However, it is in the same surface and the mitigation is the same as for dirtyfrag.

Mitigation

Same as dirtyfrag.

rmmod esp4 esp6 rxrpc
printf 'install esp4 /bin/false\ninstall esp6 /bin/false\ninstall rxrpc /bin/false\n' > /etc/modprobe.d/dirtyfrag.conf
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