The flow_dissector feature in the Linux kernel 4.3 through 5.x before 5.3.10 has a device tracking vulnerability, aka CID-55667441c84f. This occurs because the auto flowlabel of a UDP IPv6 packet relies on a 32-bit hashrnd value as a secret, and because jhash (instead of siphash) is used. The hashrnd value remains the same starting from boot time, and can be inferred by an attacker. This affects net/core/flow_dissector.c and related code.

Affected Package

OS OS Version Package Name Package Version
ubuntu upstream linux-hwe-5.8 5.4~rc6
ubuntu upstream linux-gke-5.4 5.4~rc6
ubuntu upstream linux-gkeop-5.4 5.4~rc6
ubuntu upstream linux 5.4~rc6
ubuntu 14.04 linux any
ubuntu 16.04 linux 4.4.0-170.199
ubuntu 18.04 linux 4.15.0-74.84
ubuntu 19.04 linux 5.0.0-38.41
ubuntu 19.10 linux 5.3.0-24.26
ubuntu upstream linux-dell300x 5.4~rc6
ubuntu upstream linux-gkeop 5.4~rc6
ubuntu upstream linux-oem-5.10 5.4~rc6
ubuntu 18.04 linux-aws 4.15.0-1057.59
ubuntu 19.10 linux-aws 5.3.0-1008.9
ubuntu upstream linux-aws 5.4~rc6
ubuntu 16.04 linux-aws 4.4.0-1099.110
ubuntu 16.04 linux-hwe 4.15.0-74.83~16.04.1
ubuntu 18.04 linux-hwe 5.3.0-26.28~18.04.1
ubuntu 16.04 linux-hwe-edge any
ubuntu 18.04 linux-hwe-edge any
ubuntu 14.04 linux-lts-xenial 4.4.0-170.199~14.04.1)available with ubuntu pro or ubuntu pro (infra-only
ubuntu 19.10 linux-oem 4.15.0-1066.76
ubuntu upstream linux-oem 5.4~rc6
ubuntu 16.04 linux-oem any
ubuntu upstream linux-oem-5.6 5.4~rc6
ubuntu upstream linux-aws-5.0 5.4~rc6
ubuntu upstream linux-aws-5.3 5.4~rc6
ubuntu upstream linux-aws-5.4 5.4~rc6
ubuntu upstream linux-aws-hwe 5.4~rc6
ubuntu 16.04 linux-aws-hwe 4.15.0-1057.59~16.04.1
ubuntu 19.10 linux-azure 5.3.0-1008.9
ubuntu 14.04 linux-azure 4.15.0-1066.71~14.04.1)available with ubuntu pro or ubuntu pro (infra-only
ubuntu upstream linux-azure 5.4~rc6
ubuntu 16.04 linux-azure 4.15.0-1066.71
ubuntu upstream linux-azure-4.15 5.4~rc6
ubuntu upstream linux-azure-5.3 5.4~rc6
ubuntu upstream linux-azure-5.4 5.4~rc6
ubuntu upstream linux-azure-edge 5.4~rc6
ubuntu 19.10 linux-gcp 5.3.0-1009.10
ubuntu upstream linux-gcp 5.4~rc6
ubuntu 16.04 linux-gcp 4.15.0-1052.56
ubuntu upstream linux-gcp-4.15 5.4~rc6
ubuntu upstream linux-gcp-5.3 5.4~rc6
ubuntu upstream linux-gcp-5.4 5.4~rc6
ubuntu upstream linux-gcp-edge 5.4~rc6
ubuntu upstream linux-gke-4.15 5.4~rc6
ubuntu upstream linux-gke-5.0 5.4~rc6
ubuntu upstream linux-gke-5.3 5.4~rc6
ubuntu upstream linux-hwe-5.4 5.4~rc6
ubuntu 19.10 linux-kvm 5.3.0-1008.9
ubuntu upstream linux-kvm 5.4~rc6
ubuntu 16.04 linux-kvm 4.4.0-1063.70
ubuntu 19.10 linux-oem-osp1 5.0.0-1033.38
ubuntu upstream linux-oem-osp1 5.4~rc6
ubuntu 19.10 linux-oracle 5.3.0-1007.8
ubuntu upstream linux-oracle 5.4~rc6
ubuntu 16.04 linux-oracle 4.15.0-1031.34~16.04.1
ubuntu upstream linux-oracle-5.0 5.4~rc6
ubuntu upstream linux-oracle-5.3 5.4~rc6
ubuntu upstream linux-oracle-5.4 5.4~rc6
ubuntu upstream linux-raspi 5.4~rc6
ubuntu upstream linux-raspi-5.4 5.4~rc6
ubuntu 19.10 linux-raspi2 5.3.0-1014.16
ubuntu 20.04 linux-raspi2 any
ubuntu upstream linux-raspi2 5.4~rc6
ubuntu 16.04 linux-raspi2 4.4.0-1126.135
ubuntu upstream linux-raspi2-5.3 5.4~rc6
ubuntu upstream linux-riscv 5.4~rc6
ubuntu upstream linux-snapdragon 5.4~rc6
ubuntu 16.04 linux-snapdragon 4.4.0-1130.138