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Security incidents tagged Firecracker. Newest first.
› Linux kernel networking (host side of KVM/Firecracker and similar)
Paulos Yibelo / pwn.ai found a Critical Linux networking flaw (CVE-2026-99999, CVSS 9.3) during Vercel’s $1M Sandbox challenge. Guest-controlled checksum metadata can rewrite an IPv4 header after validation, enabling host-memory disclosure and, in lab conditions, guest-to-host code execution on KVM/Firecracker. Upstream fix merged Oct 2026; host kernels need patch + reboot. Affects multi-tenant VPS / sandbox providers more than end-user desktops.
PwnEscape-Ai Research: Guest-to-Host KVM Escape (CVE-2026-99999). TLDR;- How a $1 million sandbox challenge led us to a vulnerability in Linux networking, repeatable host-memory disclosure, and ultimately a full guest-to-host escape. Blog:- t.co/CJERkG4rsE t.co/gdXbOvkklw
How can one obtain such a great identifier as CVE-2026-99999? #PwnEscape
Just uncovered: the “PwnEscape” Linux kernel flaw (CVE-2026-99999) lets guest VMs read host memory. A 9.3/10 critical issue, exposed via crafted packets in Vercel’s sandbox and patched in recent kernel versions. If you run shared Linux hosts, updating is mandatory. t.co/mqBjjVqe1d
