Troed Sångbergtroed@swecyb.com
Oct 16, 2026, 8:10 AMretooted Larvitz :fedora:
Heads up for fellow Linux admins: CVE-2026-99999 (dubbed "PwnEscape") is out, and it is a nasty one (CVSS 9.3).
Despite being called a KVM escape, the actual bug lives in the host IPv4 networking stack. Untrusted CHECKSUM_PARTIAL offload metadata from a guest can overwrite already-validated packet headers during ip_do_fragment(), leaking host memory or allowing a guest-to-host escape.
Mainline patches landed Oct 14, and stable backports are out. Check your hypervisors and reboot!