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CVE PROGRAM SOURCE RECORDUnscored

CVE-2026-98568

vxlan: use one headroom snapshot for neighbour replies

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Status
Published
Published
Updated
Assigning organization
Linux

Description

In the Linux kernel, the following vulnerability has been resolved: vxlan: use one headroom snapshot for neighbour replies vxlan_na_create() samples LL_RESERVED_SPACE() to size the reply skb and then samples it again to reserve headroom. A concurrent vxlan_changelink() can update needed_headroom between the two reads, creating a TOCTOU race. The second value can exceed the allocation and make the Ethernet header write out of bounds. The race is reproducible on the unpatched kernel. It occurred when vxlan_na_create() generated a neighbour reply while vxlan_changelink() changed the link headroom. KASAN caught a four-byte write two bytes beyond a 704-byte skbuff_small_head allocation. Snapshot the headroom once and use that value for both allocation and reservation.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

Linux Linux

Default version status: unaffected

  • 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa to < 45a67662bf8ce3aa5643accf98d328dfbb47eaf6affected
  • 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa to < 315d42ca39f69846662961c25dcf2bb07c350d14affected
  • 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa to < a3c5eb6e382dd426a5e7eb08608897ed57167ff7affected
  • 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa to < ff022fd9d0f0282c575e11778b96bd1b637503ebaffected
  • 4b29dba9c085a4fb79058fb1c45a2f6257ca3dfa to < 481506a756dcd828ef42391cb08f38d8d96d38fcaffected
  • d8be18c52dbc94989f6d74637b731af39cd3d902affected
  • 3927dace523706cc00f808520eaf2125dd7c07b5affected
  • 3.12.18 to < 3.13affected
  • 3.13.10 to < 3.14affected

Linux Linux

Default version status: affected

  • 3.14affected
  • 0 to < 3.14unaffected
  • 6.6.158 to ≤ 6.6.*unaffected
  • 6.12.112 to ≤ 6.12.*unaffected
  • 6.18.55 to ≤ 6.18.*unaffected
  • 7.2.9 to ≤ 7.2.*unaffected
  • 7.3 to ≤ *unaffected

References