vxlan: re-fetch eth header after route_shortcircuit()

Summary

In the Linux kernel, the following vulnerability has been resolved: vxlan: re-fetch eth header after route_shortcircuit() Before route_shortcircuit(), the eth header pointer is cached from eth_hdr(skb). Inside route_shortcircuit(), pskb_may_pull() can be called, which may reallocate skb->head. In this case, returning to vxlan_xmit() leaves the cached eth pointer pointing to freed memory, leading to a use-after-free when dereferencing eth->h_dest. Fix this by updating eth = eth_hdr(skb) after calling route_shortcircuit().

Timeline

1. Aug 28, 2026, 6:52 AM UTCCVE published
2. Oct 16, 2026, 7:19 PM UTCCISA SSVC assessment

   Exploitation: none · Automatable: yes · Technical impact: total

3. Oct 16, 2026, 7:26 PM UTCRecord last updated

Affected versions

• Linux Linux

  From ae8840825605f36f98f247323edc150e761cb64e · fixed in 6375093eb45cd7d89f1945f939eeae3b29d79f56; From ae8840825605f36f98f247323edc150e761cb64e · fixed in 1b7f7b653e3557690047c62f03b80a24ea5a58a5; From ae8840825605f36f98f247323edc150e761cb64e · fixed in bf045341dfb3e767f0ff94cf240ce3c371973bd4; From ae8840825605f36f98f247323edc150e761cb64e · fixed in 2355c8c26d2aa1b4385b369e67202e47d460d555; From ae8840825605f36f98f247323edc150e761cb64e · fixed in 1511631b7cfc4152b10a0a9d04c7a0bf2ddf4585; From ae8840825605f36f98f247323edc150e761cb64e · fixed in 1235e017aa11cf01e91b613c4c5ed6aa28934fff; From ae8840825605f36f98f247323edc150e761cb64e · fixed in c9dceac9e1c7c772c43c732fc0d325e72835801a; From ae8840825605f36f98f247323edc150e761cb64e · fixed in 1395a676ec15a0a02a2a6d86602324f2d5fd41d5

• Linux Linux

  3.10

• KernelLinux

  From 3.10.0 · fixed in 5.10.265; From 5.11.0 · fixed in 5.15.216; From 5.16.0 · fixed in 6.1.183; From 6.2.0 · fixed in 6.6.151; From 6.7.0 · fixed in 6.12.103; From 6.13.0 · fixed in 6.18.44; From 6.19.0 · fixed in 7.1.8

References 8