CVE-2024-38558

/// Technical description

In the Linux kernel, the following vulnerability has been resolved:

net: openvswitch: fix overwriting ct original tuple for ICMPv6

OVS_PACKET_CMD_EXECUTE has 3 main attributes:

- OVS_PACKET_ATTR_KEY - Packet metadata in a netlink format.

- OVS_PACKET_ATTR_PACKET - Binary packet content.

- OVS_PACKET_ATTR_ACTIONS - Actions to execute on the packet.

OVS_PACKET_ATTR_KEY is parsed first to populate sw_flow_key structure

with the metadata like conntrack state, input port, recirculation id,

etc. Then the packet itself gets parsed to populate the rest of the

keys from the packet headers.

Whenever the packet parsing code starts parsing the ICMPv6 header, it

first zeroes out fields in the key corresponding to Neighbor Discovery

information even if it is not an ND packet.

It is an 'ipv6.nd' field. However, the 'ipv6' is a union that shares

the space between 'nd' and 'ct_orig' that holds the original tuple

conntrack metadata parsed from the OVS_PACKET_ATTR_KEY.

ND packets should not no

/// Remediation

Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.

/// References