KVM Escape CVE-2026-99999

[Golum]

There is a new CVE-2026-99999 which allows to break out of KVM.

https://git.kernel.org/pub/scm/linu.../?id=32a8b0adaa18e52aaa0b246b5ffe683075354dbb

fyi @Hannes Laimer

 

[Golum]

ah it's already fixed in 7.0.14-24

Post in thread 'Proxmox Virtual Environment - Security Advisories'

Friday at 12:57

Subject: PSA-2026-00068-1: "PwnEscape" Guest-to-Host KVM Escape​

Advisory date: 2026-10-16

Packages: proxmox-kernel

Details:

Incomplete validation of network packet checksum metadata when completing the checksum calculation allowed an attacker to read host memory and write host kernel memory via the virtio network stack, allowing an escape from inside a KVM guest.

Fixed in:
- proxmox-kernel-7.0.14-24-pve(-signed)

References:
- CVE-2026-99999
- https://pwn.ai/blog/pwnescape

• ProxmoxSecurityAdvisory