CVE-2026-97965

/// Technical description

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

vxlan: initialize _md in vxlan_xmit_one()

If a VXLAN device is configured with both VXLAN_F_COLLECT_METADATA and

VXLAN_F_GBP, and a packet is transmitted through it using an external

ip_tunnel_info that lacks the IP_TUNNEL_VXLAN_OPT_BIT flag, md is left

pointing to the uninitialized _md stack variable:

if (test_bit(IP_TUNNEL_VXLAN_OPT_BIT, info->key.tun_flags)) {

if (info->options_len < sizeof(*md))

goto drop;

md = ip_tunnel_info_opts(info);

}

Because IP_TUNNEL_VXLAN_OPT_BIT is not set, md is not updated and remains

pointing to _md. Later, vxlan_build_skb() is called with md, which

eventually calls vxlan_build_gbp_hdr():

if (vxflags & VXLAN_F_GBP)

vxlan_build_gbp_hdr(vxh, md);

Inside vxlan_build_gbp_hdr(), md->gbp is read:

if (!md->gbp)

return;

gb

/// 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