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

batman-adv: fix stale receive device on merged fragments

Fragment reassembly reuses the skb from the highest-numbered buffered
fragment as the merged packet. When that fragment was received on a hard
interface which is deleted before the chain completes, the merged skb can
re-enter the receive path with a stale skb->dev and skb_iif.

batadv_batman_skb_recv() passes such merged packets through the normal
receive handlers again. DAT and bridge loop avoidance both derive the ARP
header length from skb->dev, so they can dereference the freed net_device
before the packet reaches the local mesh interface.

Refresh the receive device metadata from the current receive device before
running the packet handlers. This keeps internally reinjected merged
fragments consistent with the normal receive path after hard interface
teardown.

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Wed, 16 Sep 2026 10:45:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: batman-adv: fix stale receive device on merged fragments Fragment reassembly reuses the skb from the highest-numbered buffered fragment as the merged packet. When that fragment was received on a hard interface which is deleted before the chain completes, the merged skb can re-enter the receive path with a stale skb->dev and skb_iif. batadv_batman_skb_recv() passes such merged packets through the normal receive handlers again. DAT and bridge loop avoidance both derive the ARP header length from skb->dev, so they can dereference the freed net_device before the packet reaches the local mesh interface. Refresh the receive device metadata from the current receive device before running the packet handlers. This keeps internally reinjected merged fragments consistent with the normal receive path after hard interface teardown.
Title batman-adv: fix stale receive device on merged fragments
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
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cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-09-16T10:32:36.179Z

Reserved: 2026-09-11T19:38:34.777Z

Link: CVE-2026-89951

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-09-16T11:17:05.267

Modified: 2026-09-16T11:17:05.267

Link: CVE-2026-89951

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

No data.

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